Status pill + git-SHA asset versioning

- _origin_probe(): 3-min check of anidb.app pages/API; OK/DOWN + reason
  in GET /api/cdn and server.log ([probe] ORIGIN ...)
- header pill: upstream-site dot (red = down) + CDN dot + label;
  per-dot hover tooltips, tap -> toast legend (mobile has no hover)
- ?v={{VERSION}} injected from 'git describe --always --dirty' at
  startup; JSV reads it from its own script URL - replaces hand-bumped
  numbers (JSV/?v drift) and gives play-probes the running commit

server/app.py

@@ -7,6 +7,7 @@ Cloudflare workaround) and rewrites playlist URIs to go through itself.
 import base64
 import json
 import os
+import subprocess
 import threading
 import time
 from collections import Counter, OrderedDict
@@ -16,7 +17,7 @@ from base64 import urlsafe_b64encode, urlsafe_b64decode
 from urllib.parse import quote, urljoin, urlparse
 
 from fastapi import Body, FastAPI, HTTPException, Query, Request
-from fastapi.responses import FileResponse, JSONResponse, RedirectResponse, Response, StreamingResponse
+from fastapi.responses import FileResponse, HTMLResponse, JSONResponse, RedirectResponse, Response, StreamingResponse
 from fastapi.staticfiles import StaticFiles
 from itsdangerous import BadSignature, TimestampSigner
 
@@ -25,8 +26,28 @@ from . import db, upstream, users
 ROOT = Path(__file__).parent.parent
 app = FastAPI(title="ani-web")
 
+def _version():
+    """Cache-bust token: git short SHA (+ -dirty). The content of a commit
+    never changes, so ?v=<sha> is a correct cache key — this replaces the
+    hand-bumped ?v= number (forgetting a bump = users stuck on stale JS).
+    Every deploy restarts the process (run.sh), so the read is fresh."""
+    try:
+        v = subprocess.run(["git", "describe", "--always", "--dirty"], cwd=ROOT,
+                           capture_output=True, text=True, timeout=5).stdout.strip()
+        if v:
+            return v
+    except Exception:
+        pass
+    return "dev"
+
+
+VERSION = _version()
+
 # latest probe result + last 20 samples (~1h at 3-min spacing), for GET /api/cdn
 _CDN = {"state": "unknown", "kbps": 0.0, "ts": 0.0, "hist": []}
+# origin (anidb.app pages/API) health — separate host, separate failure mode
+# (observed 2026-09-03: CDN fine while origin 503'd "Under Maintenance")
+_ORIGIN = {"state": "unknown", "msg": "", "ts": 0.0}
 
 
 def _cdn_probe():
@@ -62,16 +83,34 @@ def _cdn_probe():
         _CDN.update(state=now, kbps=round(kbps), ts=time.time())
         _CDN["hist"].append({"t": time.time(), "kbps": round(kbps)})
         del _CDN["hist"][:-20]
+        _origin_probe()
         time.sleep(180)
 
 
+def _origin_probe():
+    """Hit the same kind of page users load (details page) every 3 min and
+    track OK/DOWN — this is the host that 503s 'Under Maintenance'.
+    ponytail: one URL, no history; the log line + ts tell the when."""
+    try:
+        r = upstream._get("https://anidb.app/anime/jujutsu-kaisen-season-2-2554",
+                          timeout=10)
+        state, msg = "OK", f"http {r.status_code}"
+    except Exception as e:
+        state, msg = "DOWN", str(e)
+    prev = _ORIGIN["state"]
+    _ORIGIN.update(state=state, msg=msg, ts=time.time())
+    if state != prev:
+        print(f"[probe] ORIGIN {state} ({msg})", flush=True)
+
+
 threading.Thread(target=_cdn_probe, daemon=True).start()
 
 
 @app.get("/api/cdn")
 async def cdn_status():
-    """CDN health (read-only, public): latest probe + ~1h of history."""
-    return _CDN
+    """CDN + origin health (read-only, public). Top-level fields are the CDN
+    probe (existing shape); .origin is the anidb.app pages/API probe."""
+    return {**_CDN, "origin": _ORIGIN}
 
 # ---------- auth: multi-user, signed cookies ----------
 users.migrate_legacy()  # file-based legacy import; db.init() absorbs its output
@@ -621,4 +660,15 @@ def stream(token: str):
     return Response(body, media_type=ct, headers=_STREAM_CACHE_HDRS)
 
 
+@app.get("/", include_in_schema=False)
+@app.get("/index.html", include_in_schema=False)
+def index():
+    # index.html is served (not mounted) so ?v={{VERSION}} becomes the git
+    # SHA at startup; other statics go through the mount below
+    return HTMLResponse(_INDEX_HTML.replace("{{VERSION}}", VERSION))
+
+
+_INDEX_HTML = (ROOT / "static" / "index.html").read_text()
+
+
 app.mount("/", StaticFiles(directory=ROOT / "static", html=True), name="static")