chore: Set backend.embedded to true for all-in-one packaging

The embedded flag must be true for the portable exe to work.
When embedded is false, the app expects an external backend.

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/run_server.py

@@ -26,7 +26,8 @@ def load_config(config_path: str | None = None) -> dict:
         config_path = os.path.join(base_dir, "config.json")
 
     if os.path.exists(config_path):
-        with open(config_path, "r", encoding="utf-8") as f:
+        # Use utf-8-sig to handle Windows BOM (Byte Order Mark)
+        with open(config_path, "r", encoding="utf-8-sig") as f:
             return json.load(f)
     return {}
 

client/config.json

@@ -8,7 +8,7 @@
     "compute": "int8"
   },
   "backend": {
-    "embedded": false,
+    "embedded": true,
     "host": "127.0.0.1",
     "port": 8000,
     "database": {