feat(dispatch): port triage to harness CEL trigger

[ifireball]

What is missing

triage routing logic lives in bash in reusable-dispatch.yml. It is not expressed as a CEL trigger: on the harness file, so routing cannot be customized without editing shared dispatch bash.

What should happen

One vertical PR ports triage only:

Harness

• Add trigger: CEL expressing today's bash routing for: ready-for-triage, /fs-triage, needs-info re-triage
• CEL lint/type-check in the same PR

Gating

• Decide triage-specific gates (may differ from GCD): what moves into fullsend dispatch, what stays in workflow, whether new ADR or harness format extension is needed
• Decide whether roles: config check still applies for triage in a custom-agents world

Workflow

• harness-dispatch handles triage when CEL matches
• Bash route still runs in parallel for shadow/diff until cutover epic child
• Do not remove bash routing for triage in this PR

Tests (same PR)

• Extend behaviour scenarios from test(behaviour): add triage dispatch trigger scenarios (bash routing) #2890 to cover harness-dispatch path
• Unit parity golden: normative fixtures for triage events match bash routing

Prerequisites

• feat(dispatch): add harness-dispatch job with ADR 54 auth, kill switch, and custom-agent behaviour test #2889 (harness-dispatch + custom agent)
• test(behaviour): add triage dispatch trigger scenarios (bash routing) #2890 (triage bash trigger behaviour baseline)

Merge criterion

triage behaviour scenarios green on harness-dispatch; shadow diff shows parity with bash for its trigger set.

Related

Part of epic #2888

[fullsend-ai-triage]

🤖 Finished Triage · ✅ Success · Started 8:34 AM UTC · Completed 8:37 AM UTC
Commit: 9f4f2b6 · View workflow run →

[fullsend-ai-triage]

Triage Summary

This issue is well-specified — it ports the triage agent's bash routing logic to a CEL trigger: in the harness file, as part of the broader ADR 0061 CEL dispatch epic (#2888).

However, progress is blocked on two open prerequisites that the issue itself identifies:

• feat(dispatch): add harness-dispatch job with ADR 54 auth, kill switch, and custom-agent behaviour test #2889 — adds the harness-dispatch job with ADR 54 auth, kill switch, and custom-agent behaviour tests. This provides the dispatch infrastructure that CEL triggers plug into.
• test(behaviour): add triage dispatch trigger scenarios (bash routing) #2890 — establishes the triage bash trigger behaviour baseline scenarios. These are the golden fixtures this PR's tests must match for parity.

Both are still open with no PRs in flight. Once they land, a developer can proceed with the CEL trigger definition, gating decisions, and shadow-diff testing outlined in the checklist.

Marking as blocked until prerequisites are resolved.

Blocked by:

• feat(dispatch): add harness-dispatch job with ADR 54 auth, kill switch, and custom-agent behaviour test #2889
• test(behaviour): add triage dispatch trigger scenarios (bash routing) #2890