Fix Vertex AI cassette to use CI environment values

The cassette was recorded with local project (ck-nest-dev) and location
(us-central1), but CI uses pydantic-ai project with global location.

Updated cassette to match CI environment:
- Project: ck-nest-dev → pydantic-ai
- Location: us-central1 → global
- Host: us-central1-aiplatform.googleapis.com → aiplatform.googleapis.com

This fixes the CannotOverwriteExistingCassetteException in CI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: conradlee

tests/models/cassettes/test_google/test_google_recursive_schema_native_output_gemini_2_5.yaml

@@ -57,7 +57,7 @@ interactions:
       content-type:
       - application/json
       host:
-      - us-central1-aiplatform.googleapis.com
+      - aiplatform.googleapis.com
     method: POST
     parsed_body:
       contents:
@@ -86,7 +86,7 @@ interactions:
         responseMimeType: application/json
         responseModalities:
         - TEXT
-    uri: https://us-central1-aiplatform.googleapis.com/v1beta1/projects/ck-nest-dev/locations/us-central1/publishers/google/models/gemini-2.5-flash:generateContent
+    uri: https://aiplatform.googleapis.com/v1beta1/projects/pydantic-ai/locations/global/publishers/google/models/gemini-2.5-flash:generateContent
   response:
     headers:
       alt-svc: