Show SPA e621 request times in the status pill

- New e621 metrics store tracks request count, cumulative time and the
  last request (path + duration) for the session
- The e621 client measures each request around fetch and JSON parsing
- Status pill appends a teal 'e621: <total>' segment with a tooltip
  showing request count and the last request; a server-side e621 time
  is shown separately if the backend ever reports one

frontend/src/components/StatusPill.tsx

@@ -2,6 +2,7 @@ import { Laptop, Monitor, Terminal, type LucideIcon } from "lucide-react";
 
 import { cn } from "@/lib/cn";
 import type { SystemStatus } from "@/lib/types";
+import { useE621Metrics } from "@/store/e621Metrics";
 
 const osIcons: Record<string, LucideIcon> = {
   linux: Terminal,
@@ -10,10 +11,16 @@ const osIcons: Record<string, LucideIcon> = {
 };
 
 function formatMs(value: number): string {
-  return value >= 100 ? `${Math.round(value)}ms` : `${value.toFixed(1)}ms`;
+  if (value >= 1000) return `${(value / 1000).toFixed(1)}s`;
+  if (value >= 100) return `${Math.round(value)}ms`;
+  return `${value.toFixed(1)}ms`;
 }
 
 export function StatusPill({ status }: { status?: SystemStatus }) {
+  const requestCount = useE621Metrics((state) => state.requestCount);
+  const totalMs = useE621Metrics((state) => state.totalMs);
+  const last = useE621Metrics((state) => state.last);
+
   if (!status) return null;
   const OsIcon = osIcons[status.os.icon] ?? Monitor;
 
@@ -37,10 +44,25 @@ export function StatusPill({ status }: { status?: SystemStatus }) {
       <span>{status.os.name}</span>
       <span className="text-ctp-surface2">·</span>
       <span>{formatMs(status.server_time_ms)}</span>
+      {requestCount > 0 ? (
+        <>
+          <span className="text-ctp-surface2">·</span>
+          <span
+            className="text-ctp-teal"
+            title={`${requestCount} e621 request${
+              requestCount === 1 ? "" : "s"
+            } this session · last ${last ? `${formatMs(last.ms)} (${last.path})` : "—"}`}
+          >
+            e621: {formatMs(totalMs)}
+          </span>
+        </>
+      ) : null}
       {status.e621_time_ms !== null ? (
         <>
           <span className="text-ctp-surface2">·</span>
-          <span>e621: {formatMs(status.e621_time_ms)}</span>
+          <span title="Server-side e621 time">
+            e621 (server): {formatMs(status.e621_time_ms)}
+          </span>
         </>
       ) : null}
     </span>