Assignee: Connor Turland

Summary

Adds two related session lifecycle features for smarter issue handling:

1. Base branch change notification — When a tracked base branch receives new commits via GitHub push webhooks, active sessions on that branch are notified to rebase via addStreamMessage, helping avoid merge conflicts.

2. Blocked-by dependency deferral — When Cyrus is assigned an issue with unresolved blocked_by relationships, it skips worktree/runner creation and parks the session. Parked sessions wake automatically when all blocking issues complete (or are canceled), or when a user re-prompt clears the blockers.

Implementation

Use Case 1: Base branch push notification

• Added push event type to GitHubEventTransport with new GitHubPushPayload / GitHubPushCommit types
• Created GitHubCommentWebhookEvent narrowing type to keep comment-specific utility functions type-safe
• Added getSessionsByBaseBranch(branchName, repositoryId) query to AgentSessionManager
• Added handleGitHubPushWebhook to EdgeWorker — extracts branch from refs/heads/*, finds matching repo config, looks up active sessions, builds XML notification with commit summary, streams to running session

Use Case 2: Blocked-by dependency deferral

• Added isIssueStateChangeWebhook type guard to cyrus-core for detecting stateId changes in updatedFrom
• Added parkedSessions Map to EdgeWorker (keyed by issue ID, stores all data needed to replay initializeAgentRunner)
• Added blocked-by guard in handleAgentSessionCreatedWebhook — calls checkBlockedByDependencies before starting work
• Added handleIssueStateChange handler — when blocking issues complete, removes them from parked sessions and wakes fully-unblocked sessions
• Added handleParkedSessionReprompt (Branch 1.5 in prompted handler) — re-checks blockers on user re-prompt
• Added postThoughtActivity to ActivityPoster for posting acknowledgments

Files Changed

• packages/github-event-transport/src/types.ts — Push event types, comment-narrowing types
• packages/github-event-transport/src/index.ts — New exports
• packages/github-event-transport/src/GitHubEventTransport.ts — Push event processing
• packages/github-event-transport/src/GitHubMessageTranslator.ts — Type narrowing for event type
• packages/github-event-transport/src/github-webhook-utils.ts — Narrowed to GitHubCommentWebhookEvent
• packages/core/src/issue-tracker/types.ts — isIssueStateChangeWebhook type guard
• packages/core/src/index.ts — New export
• packages/edge-worker/src/EdgeWorker.ts — All handler logic (push, blocked-by, parked sessions, wake-up)
• packages/edge-worker/src/AgentSessionManager.ts — getSessionsByBaseBranch query
• packages/edge-worker/src/ActivityPoster.ts — postThoughtActivity method

Testing

• 12 new tests added:
  • 5 tests for getSessionsByBaseBranch (AgentSessionManager.base-branch-sessions.test.ts)
  • 7 tests for isIssueStateChangeWebhook (EdgeWorker.issue-state-change.test.ts)
• All 640 edge-worker tests pass
• All package tests pass (pnpm test:packages:run)
• TypeScript type checking clean (pnpm typecheck)

Linear Issue

CYPACK-978: Base branch change notification + blocked-by dependency deferral