Adds a cached_content field on ChatGoogle (and a per-call kwarg on
ainvoke) that gets threaded into the GenerateContentConfigDict before
each generate_content call. This lets callers point Gemini at an
explicit CachedContent resource (e.g. "cachedContents/abc123") instead
of relying on implicit caching, which is constrained by the ~5-minute
TTL window.
Token accounting already pulls cached_content_token_count from
response.usage_metadata into ChatInvokeUsage.prompt_cached_tokens, so
the savings show up in usage stats without further work.
Cache creation itself (client.caches.create) is left to the caller —
this PR only adds the forwarding hook so explicit caching becomes
opt-in usable. A follow-up can wire agent-side cache lifecycle if
useful.
- add gemini-3-flash-preview-lite to VerifiedGeminiModels and token mappings
- list both gemini-3-flash-preview[-lite] alongside existing -latest aliases in CLOUD.md and api-v2.md SupportedLLMs
- swap example code and recommendations (examples/, AGENTS.md, quickstart.md, bug report placeholder) to gemini-3-flash-preview / -lite
- update Google CI test + evaluate_tasks judge LLM to gemini-3-flash-preview / -lite
Magnus Müller