Add evalops/chat to fanout-proto-bump.yml — heaviest consumer missing from automation

[haasonsaas]

Problem

`evalops/chat` is the heaviest proto consumer in the org — its Go backend imports 10 proto packages via Connect-RPC:

• memory/v1, audit/v1, keys/v1, approvals/v1, governance/v1, meter/v1, prompts/v1, registry/v1, skills/v1, identity/v1

But chat is not in the `fanout-proto-bump.yml` matrix. It currently sits 31 commits behind v0.2.0 at `v0.0.0-20260414193513-3db7075bd55b`.

Proto bumps to chat must be done manually, which means they don't happen — the gap grows silently.

Suggested fix

Add `chat` to the fanout matrix in `.github/workflows/fanout-proto-bump.yml`:

matrix:
  repo:
    - chat   # ← add this
    # ... existing repos

Also bump chat to the latest proto version immediately to close the 31-commit gap.

Context

Chat's Go backend also has its own `backend/proto/` directory for chat-specific services. These are separate from the shared proto contracts and should not be affected by the fanout.

Severity

High — the most important consumer is drifting from the proto contract.