fix: sshfs polling, WebSocket broadcast, prompt progress bar, resizable stats panel

- log_watcher: add --reopen-log mode (close/reopen each poll) for sshfs/network
  filesystems; fix nonlocal clients bug causing UnboundLocalError on first broadcast;
  fix list(clients) copy to prevent RuntimeError on concurrent set mutation
- log_parser: capture progress=X.XX from prompt timing lines into Metrics.prompt_progress
- frontend: show progress bar during processing_prompt state with PROMPT N% label;
  widen stats panel to 300px; remove model name truncation; add drag handle on
  right border of stats panel to resize between 280px–840px

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server.py

@@ -17,7 +17,7 @@ FRONTEND_DIR = Path(__file__).parent / "frontend"
 
 # ── App factory ───────────────────────────────────────────────────────────────
 
-def create_app(log_path: str) -> FastAPI:
+def create_app(log_path: str, reopen_log: bool = False) -> FastAPI:
     app = FastAPI()
     app.mount("/static", StaticFiles(directory=FRONTEND_DIR), name="static")
 
@@ -41,11 +41,11 @@ def create_app(log_path: str) -> FastAPI:
             clients.discard(ws)
 
     async def broadcast(state: ServerState):
-        nonlocal last_state
+        nonlocal last_state, clients
         last_state = state.to_dict()
         payload = json.dumps(last_state)
         dead: set[WebSocket] = set()
-        for ws in clients:
+        for ws in list(clients):
             try:
                 await ws.send_text(payload)
             except Exception:
@@ -63,7 +63,7 @@ def create_app(log_path: str) -> FastAPI:
 
     @app.on_event("startup")
     async def startup():
-        watcher = LogWatcher(log_path, on_line, on_offline=on_offline)
+        watcher = LogWatcher(log_path, on_line, on_offline=on_offline, reopen=reopen_log)
         watcher.start()
 
     return app
@@ -71,6 +71,13 @@ def create_app(log_path: str) -> FastAPI:
 
 # ── CLI entry point ───────────────────────────────────────────────────────────
 
+def _config_bool(key: str) -> bool:
+    config_file = Path("config.json")
+    if config_file.exists():
+        return bool(json.loads(config_file.read_text()).get(key, False))
+    return False
+
+
 def resolve_log_path(cli_log: Optional[str]) -> str:
     path = cli_log or os.environ.get("LLAMAGOCHI_LOG")
     if not path:
@@ -92,9 +99,12 @@ def main():
     ap = argparse.ArgumentParser(description="Llamagochi — llama-server virtual pet")
     ap.add_argument("--log", help="Path to llama-server log file")
     ap.add_argument("--port", type=int, default=8080, help="HTTP port (default: 8080)")
+    ap.add_argument("--reopen-log", action="store_true",
+                    help="Close and reopen log file each poll cycle (for sshfs/network filesystems)")
     args = ap.parse_args()
     log_path = resolve_log_path(args.log)
-    app = create_app(log_path)
+    reopen_log = args.reopen_log or _config_bool("reopen_log")
+    app = create_app(log_path, reopen_log=reopen_log)
     uvicorn.run(app, host="0.0.0.0", port=args.port)