feat: Migrate all roles to Gemini 2.0 Flash, verify RAG stability

test_gemini.py

@@ -0,0 +1,27 @@
+
+import sys
+import os
+sys.path.insert(0, '/app')
+from lib.embedding_providers.openrouter_provider import OpenRouterProvider
+from config import get_settings
+
+def test_gemini():
+    print("Testing Gemini via OpenRouter...")
+    settings = get_settings()
+    key = settings.openrouter_api_key
+    provider = OpenRouterProvider(api_key=key)
+    available_models = [
+        "google/gemini-2.0-flash-exp:free",
+        "google/gemini-2.0-flash-001"
+    ]
+    
+    for m in available_models:
+        print(f"\n🧪 Testing {m}...")
+        try:
+            resp = provider.get_completion(prompt="Hi", model=m)
+            print(f"✅ Works! {resp[:20]}")
+        except Exception as e:
+            print(f"❌ Failed: {e}")
+
+if __name__ == "__main__":
+    test_gemini()