chore(tools): regenerate the stale tool metadata

`bun run tool-metadata:check` has been failing on staging since #6317, so every PR
branched off it inherits a red CI regardless of its own contents. Reproduced against a
clean `origin/staging` to confirm it is not this branch's doing.

#6317 rewrote the embeddings tools' `apiKey` descriptions from provider-specific strings
to one generic string in `tools/embeddings/factory.ts`, but did not regenerate
`tools/generated/tool-metadata.ts`. The whole delta is 89 bytes of description text — the
tool set is unchanged at 4380 ids, none added, none removed:

    - "description":"Cohere Embeddings API key"
    + "description":"API key for the selected embedding provider"

The old strings no longer exist anywhere in source, so the generated file was the stale
side. `tool-metadata:check` passes after regenerating, and the generator's own resolver
cross-check agrees.

`mship:check` and `mship-tools:check` also fail locally, but neither is a CI gate and both
fail only because they read contracts from the sibling copilot repo, which is not checked
out here. Left alone.

Author: waleedlatif1