* feat(gemini): accept file content blocks with video_metadata on multimodal embeddings
* test(gemini): annotate the embedding mock helper and keep the type comment short
* fix(gemini-embeddings): keep file blocks through a partial embedding cache hit and validate video_metadata strictly
* test(caching): type the partial-hit cache test and pin its clock
* fix(gemini-embeddings): accept the Files API URI /v1/files returns as a file block's file_id
* fix(gemini-embeddings): 400 on bad input shapes, drop unknown block keys under drop_params, cache multi-block inputs
A bare object `input` answered 500 from both the caching handler and the
transformation; both now answer 400. An unresolved `files/` reference on
vertex_ai/ answered a ValueError 500; it now answers 400 naming the gemini/
provider. An empty `format` passed through to the provider; it now answers 400
naming file.format. Unknown block keys (`detail`, an unknown video_metadata
key, a top-level block key) are dropped under drop_params, global or
per-request, and still answer 400 without it. The embedding cache counted
file blocks against `max_messages`, so a request with 5 or more blocks was
never cached; file blocks no longer count.
* fix(caching): answer 400 for an object embedding input on the cache lookup
* test(gemini-embeddings): annotate the new embedding tests with return types and Final
* test(gemini-embeddings): annotate the transformation and files batch tests with return types and Final
* test(gemini-embeddings): audit file content blocks on the wire, in the cache, in batch uploads and under chaos
Integration cells for gemini/ and vertex_ai/ embedding file blocks with video_metadata: the batchEmbedContents and embedContent wire shapes, format overrides, nested and repeated inputs, every malformed block answering 400 before any provider call, drop_params at the request, deployment and YAML levels, the OpenAI SDK sync and async clients, Redis cache fills, hits, partial hits and the metadata in the key with zero-spend hit rows, chat, responses and messages controls, the vertex_ai/ batch JSONL upload, a mixed fast/slow/malformed/dropped burst and a worker kill. The wire peer now reads chunked request bodies, which the streamed GCS media upload sends
* test(integration): treat an upload the client abandons before its terminating chunk as a disconnect, never a stored request
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Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
