add tmux team observer + member lifecycle events (T-139, D-75)

team_observer.dart is the single drift-containment point for Claude
Code's experimental tmux team mode. It discovers the active team for a
workspace (~/.claude/teams/<team>/config.json, matched by member cwd),
polls `tmux -L clide list-panes -a`, and correlates live panes with the
config's tmuxPaneId to emit TeamMemberBorn / TeamMemberDied — identity
(name, agentType, model, colour, pane) comes from the config, so it's
reliable regardless of transcript drift.

Each teammate's subagent transcript is resolved best-effort and streamed
on a per-agent MessageBus channel via TranscriptPublisher (TranscriptReader
gains an explicit `file:` for this). The config<->transcript join is the
fragile part: no shared key, so it uses a sibling .meta.json agentType
when present, else zips members-by-joinedAt against files-by-mtime. This
join needs validation against a live team run.

App wiring + visible surfacing land with the teammate tiles (T-140).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.pql/changelog/ticket_history/2026-05.sql

@@ -2148,3 +2148,5 @@ INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by,
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-143', 'status', 'backlog', 'in_progress', NULL, '2026-05-22 22:31:25', '2026-05-22 22:31:25', '2026-05-22 22:31:25', NULL, 'e2a16eb8af0afc30a5d0fc88c523e507', 1) ON CONFLICT(hash) DO NOTHING;
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-143', 'status', 'in_progress', 'done', NULL, '2026-05-22 22:36:09', '2026-05-22 22:36:09', '2026-05-22 22:36:09', NULL, '9b8859ea2e8db7083bfb9d2ab17c1c57', 1) ON CONFLICT(hash) DO NOTHING;
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-144', 'status', 'backlog', 'in_progress', NULL, '2026-05-22 22:41:28', '2026-05-22 22:41:28', '2026-05-22 22:41:28', NULL, 'eda6f75e88401ee5b445e7edfc312f82', 1) ON CONFLICT(hash) DO NOTHING;
+INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-144', 'status', 'in_progress', 'done', NULL, '2026-05-22 22:43:45', '2026-05-22 22:43:45', '2026-05-22 22:43:45', NULL, 'da17b2710e17b1821882d47724790cbb', 1) ON CONFLICT(hash) DO NOTHING;
+INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-139', 'status', 'backlog', 'in_progress', NULL, '2026-05-22 22:50:41', '2026-05-22 22:50:41', '2026-05-22 22:50:41', NULL, 'ad063f0c3c65e5b35d3dcea036412ad9', 1) ON CONFLICT(hash) DO NOTHING;

.pql/changelog/tickets/2026-05.sql

@@ -2493,3 +2493,5 @@ INSERT INTO tickets (id, type, parent_id, title, description, status, priority,
 INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-143', 'task', 'T-132', 'Distinguish user message cards in the conversation', 'User messages render flat (label + text on the canvas) like Claude''s responses, so it''s hard to scan what you said vs what Claude said. Give UserMessage a distinct card: a filled background (globalBackground vs the panelBackground canvas), a left accent stripe (globalFocus), padding and rounded corners. Claude''s text responses stay flat markdown (better for long answers). conversation_view.dart _ConversationTurn.', 'in_progress', 'low', NULL, NULL, NULL, '2026-05-22 22:31:22', '2026-05-22 22:31:25', NULL, 'efa90d878f79235f81d54d00c04014c8', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
 INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-143', 'task', 'T-132', 'Distinguish user message cards in the conversation', 'User messages render flat (label + text on the canvas) like Claude''s responses, so it''s hard to scan what you said vs what Claude said. Give UserMessage a distinct card: a filled background (globalBackground vs the panelBackground canvas), a left accent stripe (globalFocus), padding and rounded corners. Claude''s text responses stay flat markdown (better for long answers). conversation_view.dart _ConversationTurn.', 'done', 'low', NULL, NULL, NULL, '2026-05-22 22:31:22', '2026-05-22 22:36:09', NULL, '11ebd7f43b4371b15acb0729010cdec9', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
 INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-144', 'task', 'T-132', 'Claude message card with brand-orange accent', 'Extend the distinct-card treatment (T-143) to Claude''s text responses with a different accent: Claude''s brand coral-orange (#D97757), vs the user card''s focus-colour stripe. Refactor _userCard into a shared _messageCard(label, accent, body). conversation_view.dart.', 'in_progress', 'low', NULL, NULL, NULL, '2026-05-22 22:40:42', '2026-05-22 22:41:28', NULL, '4c0eebba4edb4394fb47ba2d81ef42ad', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
+INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-144', 'task', 'T-132', 'Claude message card with brand-orange accent', 'Extend the distinct-card treatment (T-143) to Claude''s text responses with a different accent: Claude''s brand coral-orange (#D97757), vs the user card''s focus-colour stripe. Refactor _userCard into a shared _messageCard(label, accent, body). conversation_view.dart.', 'done', 'low', NULL, NULL, NULL, '2026-05-22 22:40:42', '2026-05-22 22:43:45', NULL, '1ce891624631502279b0356c5cdffae2', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
+INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-139', 'task', 'T-132', 'tmux team observer (lifecycle + identity + per-teammate transcripts)', 'New lib/builtin/claude/src/team_observer.dart: detect teammate spawn/exit (control-mode or list-panes -a poll on -L clide), map pane->teammate via ~/.claude/teams config + agentId, spin a TranscriptReader per teammate, emit new TeamMemberBorn/TeamMemberDied ClideEvents (lib/kernel/src/events/types.dart). ALL fragile CC-internals parsing isolated here (single drift-containment point; key off the version field). Cite D-75. Acceptance: a real team run emits born/died with correct identity; per-teammate content streams. Blocked by T2, T4.', 'in_progress', 'high', NULL, NULL, NULL, '2026-05-22 15:59:34', '2026-05-22 22:50:41', NULL, 'a5f4b20a0a37332ab35de8fa07e22298', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);