Publish generated TypeScript and Python clients as SDK packages

[haasonsaas]

Problem

The proto repo generates typed clients in three languages (gen/go, gen/ts, gen/python), but only Go consumers can easily import them via Go modules. TypeScript and Python consumers must either:

• Vendor the generated code manually
• Reference the proto repo as a git dependency
• Re-generate locally

This friction slows adoption for agent framework developers who work in TypeScript or Python, and it's the root cause of version drift issues like evalops/chat#948 (@bufbuild/protobuf v1 vs v2 incompatibility).

Proposed solution

TypeScript: @evalops/sdk-ts on npm

The npm-publish.yml workflow already exists. Wire it to publish gen/ts as a scoped npm package on every proto tag.

• Package the Connect-ES generated stubs
• Include typed request/response builders
• Pin @bufbuild/protobuf v2 as a peer dependency (resolves chat#948 class of issues)
• Consumers install one package instead of managing codegen

Python: evalops-proto-python on PyPI

• Package gen/python as a pip-installable package
• Pin protobuf version to match what the generated code expects (resolves fermata#9239 class of issues)
• Add to the pyproject.toml that already exists in the repo

Impact

• External agent developers get typed access to the platform without MCP overhead
• Internal consumers (chat, fermata, ensemble) get version-locked dependencies instead of manual vendoring
• Proto version incompatibilities surface at install time, not runtime
• The fanout workflow (fanout-proto-bump.yml) can include version-bump PRs that update the SDK dependency in consumers

Relationship to existing issues

• evalops/chat#948 — @bufbuild/protobuf v1→v2 incompatibility would be resolved by a centrally published SDK
• evalops/fermata#9239 — Python protobuf version incompatibility would be resolved by a pinned SDK
• Add evalops/chat to fanout-proto-bump.yml — heaviest consumer missing from automation #84 — adding chat to the fanout is necessary but insufficient without a published package to bump