Fix shell details: distro name, storage path only in footer

- OS name comes from /etc/os-release (e.g. 'CachyOS Linux'), mirroring
  the original app's os_utils; macOS/Windows get proper names too
- Status pill shows the name as-is instead of uppercasing it
- Removed the watched-folder path next to the logo; it now appears only
  in the footer strip (spec updated to match)

backend/apps/core/system_info.py

@@ -0,0 +1,33 @@
+import platform
+from functools import lru_cache
+
+
+@lru_cache(maxsize=1)
+def _os_release_values():
+    values = {}
+    try:
+        with open("/etc/os-release", encoding="utf-8") as handle:
+            for line in handle:
+                line = line.strip()
+                if not line or "=" not in line:
+                    continue
+                key, value = line.split("=", 1)
+                values[key] = value.strip().strip('"')
+    except OSError:
+        pass
+    return values
+
+
+@lru_cache(maxsize=1)
+def get_os_info():
+    """OS display name and icon key, mirroring the original app's os_utils."""
+    system = platform.system()
+    release = platform.release()
+    if system == "Linux":
+        name = _os_release_values().get("NAME") or "Linux"
+        return {"name": name, "release": release, "icon": "linux"}
+    if system == "Darwin":
+        return {"name": "macOS", "release": release, "icon": "apple"}
+    if system == "Windows":
+        return {"name": "Windows", "release": release, "icon": "windows"}
+    return {"name": system, "release": release, "icon": "unknown"}

backend/apps/core/views.py

@@ -1,4 +1,3 @@
-import platform
 import time
 
 from django.conf import settings
@@ -6,13 +5,7 @@ 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}
+from .system_info import get_os_info
 
 
 def _worker_counts():
@@ -35,7 +28,7 @@ class StatusView(APIView):
             "env": settings.APP_ENV,
             "git_hash": settings.GIT_COMMIT_HASH,
             "version": settings.APP_VERSION,
-            "os": _os_info(),
+            "os": get_os_info(),
             "watched_folder": settings.WATCHED_FOLDER,
             "e621_time_ms": None,  # no e621 calls in the backend yet
             "workers": _worker_counts(),