feat(automation): do not pick issues that are not the agent's work (AGT-4682)

[unohee]

Summary

• The heartbeat treated every Todo/Backlog issue of an enabled project as work for the swarm (includeBacklog defaults to true). Moving 13 stale human-owned cards to Backlog made the daemon queue one at once and defer four more.
• New autonomous.skip rules, applied right after the fetch and before filterAlreadyProcessed so neither selection nor idle fill (which lives in that filter) sees them:
  • a skip label (default swarm:skip, compared case-insensitively),
  • an epic: the issue has sub-issues (the Linear bulk query now fetches children(first: 1)),
  • a title tag that opens a bracket group (default 인수, 확인 원장, Docs).
• One aggregated log line per reason: not agent work (label:swarm:skip) 2: AX-1, AX-2.
• A task the operator dispatched by hand is never skipped.

Decisions worth a look

• [UAT] is not a default tag: cgf-portal's [UAT] issues are mostly defect reports the daemon fixes with real PRs. It stays configurable.
• [EPIC] is not a default tag: the decision engine's existing umbrella rule (R2) already drops a title-tagged epic. The new epics rule adds the ones that only show up as an issue with sub-issues.
• Local deployments should add their own labels to autonomous.skip.labels in config.yaml (for example the 외부 검증·결정 대기 label).

Tests

• agentEligibility.test.ts: each rule, case-insensitivity, tag boundaries, [UAT] not skipped by default, explicit dispatch never skipped, grouping and summary format.
• autonomousRunner.agentEligibility.test.ts: a real heartbeat() hands only the eligible issue to filterAlreadyProcessed and nothing to selection when none is left.
• config.test.ts (schema, hand-picked mapping, defaults), linear.test.ts (query asks for children), decisionEngine.stuck.test.ts (hasChildren reaches the task).
• Mutations: bypassing the partition fails both heartbeat tests; removing the epic, label or explicit-dispatch rule fails the matching unit test.
• Related suites pass (107 tests) and tsc --noEmit is clean. The heartbeat test needed a longer timeout on a machine at load average 300, so it carries an explicit 60 s limit.