Shell polish: storage line, status pill, footer strip, sidebar

Backend:
- apps.core with GET /api/status/ (env, git hash, OS, watched folder,
  worker counts) and a TimingMiddleware adding X-Server-Time-Ms
- status endpoint reports its own server-side assembly time

Frontend:
- top bar shows the storage line (watched folder) and a status pill
  with ENV, git hash, host OS, server time (e621 time once it exists)
- fixed 32px footer strip: storage path, active workers, build version
- collapsible filter sidebar: closed by default, Ctrl/Cmd+B toggle,
  overlay drawer with backdrop blur under 1024px
- rating filters, per-page and sidebar state persist in localStorage

backend/apps/core/apps.py

@@ -0,0 +1,5 @@
+from django.apps import AppConfig
+
+
+class CoreConfig(AppConfig):
+    name = "apps.core"

backend/apps/core/middleware.py

@@ -0,0 +1,19 @@
+import time
+
+
+class TimingMiddleware:
+    """Record server-side request time, mirroring the original app.
+
+    Sets ``request.start_time`` before the view runs so views can report
+    elapsed time, and exposes the total duration as a response header.
+    """
+
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        started = time.perf_counter()
+        request.start_time = started
+        response = self.get_response(request)
+        response["X-Server-Time-Ms"] = f"{(time.perf_counter() - started) * 1000:.1f}"
+        return response

backend/apps/core/urls.py

@@ -0,0 +1,7 @@
+from django.urls import path
+
+from .views import StatusView
+
+urlpatterns = [
+    path("status/", StatusView.as_view(), name="status"),
+]

backend/apps/core/views.py

@@ -0,0 +1,44 @@
+import platform
+import time
+
+from django.conf import settings
+from rest_framework.permissions import AllowAny
+from rest_framework.response import Response
+from rest_framework.views import APIView
+
+
+def _os_info():
+    system = platform.system()
+    icon = {"Linux": "linux", "Darwin": "apple", "Windows": "windows"}.get(
+        system, "unknown"
+    )
+    return {"name": system, "release": platform.release(), "icon": icon}
+
+
+def _worker_counts():
+    """Active/queued background jobs.
+
+    No task pipeline exists yet, so this reports honest zeros for now.
+    """
+    return {"active": 0, "queued": 0}
+
+
+class StatusView(APIView):
+    """Runtime status used by the SPA shell (storage line, status pill, footer)."""
+
+    permission_classes = [AllowAny]
+
+    def get(self, request):
+        started = getattr(request, "start_time", time.perf_counter())
+        payload = {
+            "app": "J621",
+            "env": settings.APP_ENV,
+            "git_hash": settings.GIT_COMMIT_HASH,
+            "version": settings.APP_VERSION,
+            "os": _os_info(),
+            "watched_folder": settings.WATCHED_FOLDER,
+            "e621_time_ms": None,  # no e621 calls in the backend yet
+            "workers": _worker_counts(),
+        }
+        payload["server_time_ms"] = round((time.perf_counter() - started) * 1000, 1)
+        return Response(payload)

backend/config/settings.py

@@ -52,6 +52,7 @@ INSTALLED_APPS = [
     "django_filters",
     "apps.accounts",
     "apps.library",
+    "apps.core",
 ]
 
 MIDDLEWARE = [
@@ -62,6 +63,7 @@ MIDDLEWARE = [
     "django.contrib.auth.middleware.AuthenticationMiddleware",
     "django.contrib.messages.middleware.MessageMiddleware",
     "django.middleware.clickjacking.XFrameOptionsMiddleware",
+    "apps.core.middleware.TimingMiddleware",
 ]
 
 ROOT_URLCONF = "config.urls"

backend/config/urls.py

@@ -6,6 +6,7 @@ from django.urls import include, path
 urlpatterns = [
     path("admin/", admin.site.urls),
     path("api/auth/", include("apps.accounts.urls")),
+    path("api/", include("apps.core.urls")),
     path("api/", include("apps.library.urls")),
 ]
 

frontend/src/components/AppShell.tsx

@@ -1,9 +1,15 @@
-import { LogOut } from "lucide-react";
-import { Link, NavLink, Outlet } from "react-router-dom";
+import { useQuery } from "@tanstack/react-query";
+import { LogOut, Menu } from "lucide-react";
+import { useEffect } from "react";
+import { Link, NavLink, Outlet, useLocation } from "react-router-dom";
 
+import { StatusFooter } from "@/components/StatusFooter";
+import { StatusPill } from "@/components/StatusPill";
+import { api } from "@/lib/api";
 import { cn } from "@/lib/cn";
-import { APP_VERSION } from "@/lib/version";
+import type { SystemStatus } from "@/lib/types";
 import { useAuth } from "@/store/auth";
+import { useUi } from "@/store/ui";
 
 const navItems = [
   { to: "/", label: "Library" },
@@ -13,17 +19,60 @@ const navItems = [
 export function AppShell() {
   const user = useAuth((state) => state.user);
   const logout = useAuth((state) => state.logout);
+  const toggleSidebar = useUi((state) => state.toggleSidebar);
+  const location = useLocation();
+
+  const statusQuery = useQuery({
+    queryKey: ["status"],
+    queryFn: () => api<SystemStatus>("/api/status/"),
+    refetchInterval: 30_000,
+    staleTime: 15_000,
+  });
+  const status = statusQuery.data;
+
+  useEffect(() => {
+    function handleKeyDown(event: KeyboardEvent) {
+      if ((event.ctrlKey || event.metaKey) && event.key.toLowerCase() === "b") {
+        event.preventDefault();
+        toggleSidebar();
+      }
+    }
+    window.addEventListener("keydown", handleKeyDown);
+    return () => window.removeEventListener("keydown", handleKeyDown);
+  }, [toggleSidebar]);
+
+  const showSidebarToggle = location.pathname === "/";
 
   return (
     <div className="flex min-h-screen flex-col">
       <header className="sticky top-0 z-40 border-b border-ctp-surface0 bg-ctp-crust/95 backdrop-blur">
-        <div className="mx-auto flex h-14 w-full max-w-[1600px] items-center gap-6 px-4">
-          <Link to="/" className="flex items-center gap-2.5">
+        <div className="mx-auto flex h-14 w-full max-w-[1600px] items-center gap-4 px-4">
+          <Link to="/" className="flex shrink-0 items-center">
             <span className="rounded bg-ctp-mauve px-2 py-1 font-mono text-xs font-bold tracking-wide text-ctp-crust">
               J621
             </span>
           </Link>
 
+          {status ? (
+            <span
+              className="hidden max-w-[240px] truncate font-mono text-[11px] text-ctp-overlay0 md:block"
+              title={status.watched_folder}
+            >
+              {status.watched_folder}
+            </span>
+          ) : null}
+
+          {showSidebarToggle ? (
+            <button
+              type="button"
+              onClick={toggleSidebar}
+              title="Toggle filters (Ctrl+B)"
+              className="rounded-md p-1.5 text-ctp-overlay0 transition hover:bg-ctp-surface0 hover:text-ctp-text"
+            >
+              <Menu className="h-4 w-4" />
+            </button>
+          ) : null}
+
           <nav className="flex items-center gap-1">
             {navItems.map((item) => (
               <NavLink
@@ -45,12 +94,7 @@ export function AppShell() {
           </nav>
 
           <div className="ml-auto flex items-center gap-3">
-            <span
-              className="hidden font-mono text-[11px] text-ctp-overlay0 lg:block"
-              title="Running build"
-            >
-              {APP_VERSION}
-            </span>
+            <StatusPill status={status} />
             {user ? (
               <>
                 <div className="flex items-center gap-2">
@@ -82,9 +126,11 @@ export function AppShell() {
         </div>
       </header>
 
-      <main className="mx-auto w-full max-w-[1600px] flex-1 px-4 py-6">
+      <main className="mx-auto w-full max-w-[1600px] flex-1 px-4 pb-14 pt-6">
         <Outlet />
       </main>
+
+      <StatusFooter status={status} />
     </div>
   );
 }

frontend/src/components/StatusFooter.tsx

@@ -0,0 +1,38 @@
+import { Folder, Zap } from "lucide-react";
+
+import type { SystemStatus } from "@/lib/types";
+import { APP_VERSION } from "@/lib/version";
+
+export function StatusFooter({ status }: { status?: SystemStatus }) {
+  return (
+    <footer className="fixed inset-x-0 bottom-0 z-30 border-t border-ctp-surface0 bg-ctp-crust">
+      <div className="mx-auto flex h-8 w-full max-w-[1600px] items-center gap-4 px-4 font-mono text-[11px] text-ctp-overlay0">
+        <span
+          className="flex min-w-0 items-center gap-1.5"
+          title={status?.watched_folder ?? ""}
+        >
+          <Folder className="h-3 w-3 shrink-0" />
+          <span className="hidden shrink-0 sm:inline">Local Storage:</span>
+          <span className="truncate">{status?.watched_folder ?? "…"}</span>
+        </span>
+
+        <span
+          className="hidden shrink-0 items-center gap-1.5 md:flex"
+          title="Active background jobs"
+        >
+          <Zap className="h-3 w-3" />
+          <span>
+            Active Workers:{" "}
+            {status
+              ? `${status.workers.active} running | ${status.workers.queued} pending`
+              : "…"}
+          </span>
+        </span>
+
+        <span className="ml-auto shrink-0" title="Running build">
+          {status?.version ?? APP_VERSION}
+        </span>
+      </div>
+    </footer>
+  );
+}

frontend/src/components/StatusPill.tsx

@@ -0,0 +1,48 @@
+import { Laptop, Monitor, Terminal, type LucideIcon } from "lucide-react";
+
+import { cn } from "@/lib/cn";
+import type { SystemStatus } from "@/lib/types";
+
+const osIcons: Record<string, LucideIcon> = {
+  linux: Terminal,
+  apple: Laptop,
+  windows: Monitor,
+};
+
+function formatMs(value: number): string {
+  return value >= 100 ? `${Math.round(value)}ms` : `${value.toFixed(1)}ms`;
+}
+
+export function StatusPill({ status }: { status?: SystemStatus }) {
+  if (!status) return null;
+  const OsIcon = osIcons[status.os.icon] ?? Monitor;
+
+  return (
+    <span
+      className="hidden select-none items-center gap-1.5 rounded-full border border-ctp-surface0 bg-ctp-mantle px-2.5 py-1 font-mono text-[11px] text-ctp-overlay1 lg:flex"
+      title={`${status.os.name} ${status.os.release} · built from ${status.git_hash}`}
+    >
+      <span
+        className={cn(
+          "font-medium",
+          status.env === "prod" ? "text-ctp-teal" : "text-ctp-yellow",
+        )}
+      >
+        ENV: {status.env.toUpperCase()}
+      </span>
+      <span className="text-ctp-surface2">·</span>
+      <span>{status.git_hash}</span>
+      <span className="text-ctp-surface2">·</span>
+      <OsIcon className="h-3 w-3" />
+      <span>{status.os.name.toUpperCase()}</span>
+      <span className="text-ctp-surface2">·</span>
+      <span>{formatMs(status.server_time_ms)}</span>
+      {status.e621_time_ms !== null ? (
+        <>
+          <span className="text-ctp-surface2">·</span>
+          <span>e621: {formatMs(status.e621_time_ms)}</span>
+        </>
+      ) : null}
+    </span>
+  );
+}

frontend/src/features/library/FileDetailPage.tsx

@@ -1,6 +1,6 @@
 import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
 import { ArrowLeft, Download } from "lucide-react";
-import { useEffect, useState } from "react";
+import { useState } from "react";
 import { Link, useParams } from "react-router-dom";
 
 import { Button, EmptyState, Spinner, inputClass } from "@/components/ui";
@@ -38,12 +38,6 @@ function CustomDataCard({ item }: { item: MediaItem }) {
   const [tags, setTags] = useState(item.tags.join(", "));
   const [notes, setNotes] = useState(item.notes);
 
-  useEffect(() => {
-    setRating(item.rating);
-    setTags(item.tags.join(", "));
-    setNotes(item.notes);
-  }, [item.md5, item.rating, item.tags, item.notes]);
-
   const mutation = useMutation({
     mutationFn: (payload: { rating: Rating; tags: string[]; notes: string }) =>
       api<MediaItem>(`/api/files/${item.md5}/`, {
@@ -219,7 +213,7 @@ export default function FileDetailPage() {
             </a>
           </section>
 
-          <CustomDataCard item={item} />
+          <CustomDataCard key={item.updated_at} item={item} />
 
           <section className="rounded-lg border border-ctp-surface0 bg-ctp-base p-4">
             <h2 className="text-sm font-semibold text-ctp-subtext1">

frontend/src/features/library/LibraryPage.tsx

@@ -1,11 +1,12 @@
 import { useQuery } from "@tanstack/react-query";
-import { Search } from "lucide-react";
+import { Search, X } from "lucide-react";
 import { useState, type FormEvent } from "react";
 
 import { MediaCard } from "@/components/MediaCard";
 import { Button, EmptyState, Spinner, inputClass } from "@/components/ui";
 import { api } from "@/lib/api";
 import { cn } from "@/lib/cn";
+import { useUi } from "@/store/ui";
 import type { MediaItem, Paginated } from "@/lib/types";
 
 const sortOptions = [
@@ -40,11 +41,16 @@ const ratingFilters = [
 export default function LibraryPage() {
   const [searchInput, setSearchInput] = useState("");
   const [search, setSearch] = useState("");
-  const [ratings, setRatings] = useState<string[]>([]);
   const [ordering, setOrdering] = useState("-created_at");
-  const [perPage, setPerPage] = useState(48);
   const [page, setPage] = useState(1);
 
+  const sidebarOpen = useUi((state) => state.sidebarOpen);
+  const setSidebarOpen = useUi((state) => state.setSidebarOpen);
+  const ratings = useUi((state) => state.ratings);
+  const setRatings = useUi((state) => state.setRatings);
+  const perPage = useUi((state) => state.perPage);
+  const setPerPage = useUi((state) => state.setPerPage);
+
   const query = useQuery({
     queryKey: ["files", { search, ratings, ordering, perPage, page }],
     queryFn: () => {
@@ -71,10 +77,10 @@ export default function LibraryPage() {
 
   function toggleRating(value: string) {
     setPage(1);
-    setRatings((current) =>
-      current.includes(value)
-        ? current.filter((rating) => rating !== value)
-        : [...current, value],
+    setRatings(
+      ratings.includes(value)
+        ? ratings.filter((rating) => rating !== value)
+        : [...ratings, value],
     );
   }
 
@@ -85,9 +91,8 @@ export default function LibraryPage() {
     setPage(1);
   }
 
-  return (
-    <div className="flex flex-col gap-6 lg:flex-row lg:items-start">
-      <aside className="flex w-full shrink-0 flex-col gap-5 rounded-lg border border-ctp-surface0 bg-ctp-base p-4 lg:sticky lg:top-20 lg:w-64">
+  const filterPanel = (
+    <>
       <form onSubmit={applySearch} className="flex flex-col gap-2">
         <span className="text-xs font-medium uppercase tracking-wide text-ctp-overlay1">
           Search
@@ -173,7 +178,41 @@ export default function LibraryPage() {
           ))}
         </select>
       </label>
+    </>
+  );
+
+  return (
+    <div className="flex flex-col gap-6 lg:flex-row lg:items-start">
+      {sidebarOpen ? (
+        <>
+          <div
+            className="fixed inset-0 z-40 bg-ctp-crust/60 backdrop-blur-sm lg:hidden"
+            onClick={() => setSidebarOpen(false)}
+            aria-hidden="true"
+          />
+          <aside
+            className={cn(
+              "fixed inset-y-0 left-0 z-50 flex w-72 flex-col gap-5 overflow-y-auto border-r border-ctp-surface0 bg-ctp-base p-4",
+              "lg:sticky lg:inset-y-auto lg:top-20 lg:z-auto lg:w-64 lg:shrink-0 lg:overflow-visible lg:rounded-lg lg:border",
+            )}
+          >
+            <div className="flex items-center justify-between">
+              <span className="text-sm font-semibold text-ctp-subtext1">
+                Filters
+              </span>
+              <button
+                type="button"
+                onClick={() => setSidebarOpen(false)}
+                title="Close filters"
+                className="rounded-md p-1 text-ctp-overlay0 transition hover:bg-ctp-surface0 hover:text-ctp-text lg:hidden"
+              >
+                <X className="h-4 w-4" />
+              </button>
+            </div>
+            {filterPanel}
           </aside>
+        </>
+      ) : null}
 
       <section className="min-w-0 flex-1">
         <div className="mb-4 flex items-center justify-between gap-3">

frontend/src/lib/types.ts

@@ -35,3 +35,22 @@ export interface Paginated<T> {
   previous: string | null;
   results: T[];
 }
+
+export interface SystemStatus {
+  app: string;
+  env: "dev" | "prod";
+  git_hash: string;
+  version: string;
+  os: {
+    name: string;
+    release: string;
+    icon: "linux" | "apple" | "windows" | "unknown";
+  };
+  watched_folder: string;
+  e621_time_ms: number | null;
+  workers: {
+    active: number;
+    queued: number;
+  };
+  server_time_ms: number;
+}

frontend/src/store/ui.ts

@@ -0,0 +1,29 @@
+import { create } from "zustand";
+import { persist } from "zustand/middleware";
+
+interface UiState {
+  sidebarOpen: boolean;
+  setSidebarOpen: (open: boolean) => void;
+  toggleSidebar: () => void;
+  ratings: string[];
+  setRatings: (ratings: string[]) => void;
+  perPage: number;
+  setPerPage: (perPage: number) => void;
+}
+
+export const useUi = create<UiState>()(
+  persist(
+    (set) => ({
+      sidebarOpen: false,
+      setSidebarOpen: (sidebarOpen) => set({ sidebarOpen }),
+      toggleSidebar: () => set((state) => ({ sidebarOpen: !state.sidebarOpen })),
+
+      ratings: [],
+      setRatings: (ratings) => set({ ratings }),
+
+      perPage: 48,
+      setPerPage: (perPage) => set({ perPage }),
+    }),
+    { name: "j621.ui" },
+  ),
+);