ci: seed antigravity CLI auth tokens in Cloud Build step

Author: omkargaikwad23

cloudbuild.yaml

@@ -83,6 +83,15 @@ steps:
         # Maps the decrypted DB_PASSWORD to the exact variable expected by gemini_cli and extension skills
         export CLOUD_SQL_POSTGRES_PASSWORD=$$DB_PASSWORD
 
+        # Seed agy auth: this step overrides the image ENTRYPOINT (entrypoint: bash),
+        # so entrypoint.sh never runs -- seed the token files here instead. HOME is
+        # /builder/home in a Cloud Build step, which is exactly where the harness reads.
+        AGY_DIR="$$HOME/.gemini/antigravity-cli"
+        mkdir -p "$$AGY_DIR"
+        printf '%s' "$$AGY_OAUTH_TOKEN" > "$$AGY_DIR/antigravity-oauth-token"
+        printf '%s' "$$AGY_INSTALLATION_ID" > "$$AGY_DIR/installation_id"
+        chmod 600 "$$AGY_DIR/antigravity-oauth-token" "$$AGY_DIR/installation_id"
+
         # Combine CI metadata with all available run configs
         for config in /workspace/evals/*run_config.yaml; do
           if [ -f "$config" ]; then