fix(luna-tts): load models in background thread so host responds to Chrome immediately

server/native_host.py

@@ -89,22 +89,28 @@ def _write_status(status, detail=""):
 
 def main():
     _log_stderr("[host] Starting Native Messaging host...")
-    _write_status("starting", "Loading our references...")
+    _write_status("starting", "Loading models... (may take minutes on Intel Mac)")
 
     our_dir = BASE_DIR / REFERENCE_DIRS["our"]
     competitor_dir = BASE_DIR / REFERENCE_DIRS["competitor"]
     big_vendor_dir = BASE_DIR / REFERENCE_DIRS["big_vendor"]
 
-    _write_status("starting", "Loading competitor references...")
-    _write_status("starting", "Loading big vendor references...")
+    # Load models in background while message loop responds immediately to status requests
+    import threading
+    matcher = [None]  # mutable container for thread to write into
+    load_done = threading.Event()
 
-    matcher = MultiMatcher(our_dir, competitor_dir, big_vendor_dir)
+    def _load():
+        matcher[0] = MultiMatcher(our_dir, competitor_dir, big_vendor_dir)
+        _write_status("ready", "Models loaded")
+        _log_stderr("[host] Models loaded, ready for matching")
+        load_done.set()
+
+    threading.Thread(target=_load, daemon=True).start()
 
     today_votes = 0
     today_skips = 0
     luna_votes = 0
-    _write_status("ready", f"Models loaded, {today_votes} votes today")
-    _log_stderr("[host] Ready, waiting for messages...")
 
     while True:
         data = read_message()
@@ -114,6 +120,13 @@ def main():
         msg_type = data.get("type")
 
         if msg_type == "match_request":
+            # Wait for model loading to complete
+            if not load_done.is_set():
+                _write_status("loading", "Waiting for models to load before matching...")
+                _log_stderr("[host] Waiting for models to load...")
+                load_done.wait()
+                _log_stderr("[host] Models ready, processing match request")
+
             request_id = data["request_id"]
             audio_left_url = data["audio_left"]
             audio_right_url = data["audio_right"]
@@ -148,8 +161,8 @@ def main():
                     })
                     continue
 
-                left_result = matcher.match_one(left_path)
-                right_result = matcher.match_one(right_path)
+                left_result = matcher[0].match_one(left_path)
+                right_result = matcher[0].match_one(right_path)
 
                 def _build_side(label, r):
                     our_sp, our_sc = r.our