build(vertexai): add google-genai>=1.69.0 version floor

The vertexai provider depends on GenerateContentConfig.service_tier
which was introduced in google-genai v1.69.0. Pin the minimum version
to prevent installation of older SDK versions that lack this field.

Signed-off-by: Major Hayden <major@mhtx.net>

Author: major

pyproject.toml

@@ -88,7 +88,7 @@ starter = [
     "fire",
     "fireworks-ai<=0.17.16",
     "fonttools>=4.60.2",
-    "google-genai",
+    "google-genai>=1.69.0",
     "h11>=0.16.0",
     "httpx",
     "langdetect",