Change deployment region to us-central1 for Gemini Live Native Audio

The Gemini Live Native Audio model is only available in us-central1.
Also update model name to Vertex AI GA version.

Author: oadultradeepfield

.github/workflows/ci.yml

@@ -7,7 +7,7 @@ on:
     branches: [main]
 
 env:
-  REGION: asia-southeast1
+  REGION: us-central1
   SERVICE_NAME: jemmie-backend
 
 jobs:

docs/deployment.md

@@ -142,6 +142,6 @@ gcloud projects add-iam-policy-binding $PROJECT_ID \
 Check Cloud Run timeout and session affinity settings:
 ```bash
 gcloud run services describe jemmie-backend \
-    --region=asia-southeast1 \
+    --region=us-central1 \
     --format='yaml(spec.template.spec.containers[0].env)'
 ```

src/agent/config.py

@@ -2,7 +2,7 @@
 
 from google.adk.agents.run_config import RunConfig, StreamingMode
 
-MODEL_NAME = "gemini-2.5-flash-native-audio-preview-12-2025"
+MODEL_NAME = "gemini-live-2.5-flash-native-audio"
 
 INPUT_SAMPLE_RATE = 16000
 OUTPUT_SAMPLE_RATE = 24000

tests/test_agent.py

@@ -50,7 +50,7 @@ class TestAgentConfig:
     """Tests for agent configuration."""
 
     def test_model_name(self) -> None:
-        assert MODEL_NAME == "gemini-2.5-flash-native-audio-preview-12-2025"
+        assert MODEL_NAME == "gemini-live-2.5-flash-native-audio"
 
     def test_sample_rates(self) -> None:
         assert INPUT_SAMPLE_RATE == 16000