slice 5: task-card parser + background worker

Watches topology_runs' event stream for the INT-XX marker protocol
(see skills/foundation/int-xx-marker-protocol.md) and materializes
mission_tasks rows with typed status so the canvas Tasks tab renders
a live timeline instead of raw agent chatter.

Migration 0051 adds mission_id + mission_phase_id columns to
topology_runs (nullable) so runs enqueued by a mission phase can be
attributed. Populated by future phase executors; NULL for legacy
research/loops runs (parser skips them cleanly).

New Rust surface:
  - task_card_parser::parse(text) — line-scanner over TASK/WORK/
    HANDOFF/TEST_PASS/TEST_FAIL/REVIEW_APPROVE/REVIEW_BLOCK/COMPLETED
    markers. Strict: exact kind + colon + INT- prefix, no in-prose
    matches, no bold/code-fence wrappers.
  - task_card_parser::apply_for_run(pool, run_id) — reads the run's
    mission binding, walks its event payloads, extracts text/output/
    content/message string fields (matching every ZeroClaw event
    shape we see), parses markers, UPSERTs mission_tasks via the
    (phase_id, external_id) unique key from Slice 1.
  - task_card_worker::spawn — 15s poller over runs updated in the
    last 5 minutes. Idempotent + generous window survives server
    restarts + task-scheduling jitter.

Boot wires the worker after the content loaders. Silent no-op when
mission wiring isn't populated yet.

MarkerKind → status mapping (monotonic-forward):
  TASK           → created
  WORK           → working
  HANDOFF        → validating
  TEST_PASS      → validating
  TEST_FAIL      → failed
  REVIEW_APPROVE → validating
  REVIEW_BLOCK   → failed
  COMPLETED      → complete

Follow-ups:
  - Wire phase executor to populate topology_runs.mission_id +
    mission_phase_id (Slice 6/7/8 work)
  - Assign assigned_agent_id via the event's producing agent alias
    (currently always None)
  - SSE stream on /api/missions/{id}/tasks for live canvas updates
    (currently the canvas polls via mission GET)

Co-Authored-By: Claude Opus 4.7 <[email protected]>

crates/bins/clawmates-server/src/main.rs

@@ -284,6 +284,10 @@ async fn run() -> Result<(), String> {
             eprintln!("team_template_loader: loaded {n_tpl} builtin team template(s)");
         });
     }
+    // Task-card parser worker (Slice 5): scans recent topology_runs
+    // for INT-XX markers in event payloads and upserts mission_tasks
+    // rows so the canvas renders a live status timeline.
+    cm_api::task_card_worker::spawn(pool.clone());
     // Outbound-email delivery: drains the §15-gated `outbox` over SMTP. Inert
     // until CLAWMATES_SMTP_* is set, so it ships safely before credentials exist.
     cm_runtime::spawn_drainer(pool.clone(), std::time::Duration::from_secs(10));