Sprint 18 ceremony: recall (v2)

[laynepenney]

Summary

Sprint 18 ceremony for recall repo. Replaces #680 which had merge conflicts.

Previous ceremony PR #674 already merged the bulk of sprint-18 work (channel seam hooks, SQLite lock fix, OSS protocol tests, self-contained worktree tests). This PR adds the remaining commit:

• feat: interactive web dashboard with codex support (feat: interactive web dashboard with codex support #677) — Mission Control dashboard with ANSI rendering, key palette, codex agent support, join/leave spam suppression, ephemeral agent detection in reaper

Channel spam fix (recall#677)

• Reaper no longer writes leave messages to JSONL (presence table is sufficient)
• Agents whose display_name == griptree are detected as ephemeral and fully cleaned up
• Dashboard renderer returns empty string for join/leave events

Premium boundary: core OSS (channel infrastructure, dashboard).

Test plan

• pytest tests/recall/test_channel.py passes
• Dashboard renders without join/leave spam
• Full test suite green

Generated with Claude Code

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