missions: phase-completion summary card (Claude Opus 4.8 synthesized)

New phase_summarizer background worker fires on any mission_phase
transition to a terminal state (completed/failed). Aggregates every
topology_runs.checkpoint.outputs[] + mission_tasks + mission_artifacts
bound to that phase and asks Claude Opus 4.8 to produce a structured
JSON card:

  { narrative, metrics, sources, tooling, next_actions }

Rendered inline on the mission page under each completed phase via
new PhaseSummaryCard component. Metrics grid is kind-specific:
research surfaces insights/sources/int_cards/artifacts, coding
surfaces cards_picked_up/commits/tests/issues, benchmark surfaces
regressions/improvements, security surfaces findings-by-severity.

New table: mission_phase_summaries (migration 0060), unique per
phase_id — regenerates on retry.
New endpoint: GET /api/missions/{id}/phases/{phase_id}/summary.

Model overridable via CLAWMATES_SUMMARIZER_MODEL. Reuses the
ANTHROPIC_API_KEY prod already carries for mission_refiner.

frontend/src/components/dashboard/MissionCanvas.tsx

@@ -37,6 +37,7 @@ import { MissionLivePane } from "./MissionLivePane";
 import { MissionTeamTab } from "./MissionTeamTab";
 import { MissionWizard } from "./MissionWizard";
 import { PhaseRunsList } from "./PhaseRunsList";
+import { PhaseSummaryCard } from "./PhaseSummaryCard";
 import { RefineDiffModal } from "./RefineDiffModal";
 
 const mono =
@@ -681,6 +682,9 @@ export function MissionCanvas({
                     </span>
                   )}
                   <PhaseRunsList runs={runsByPhase.get(p.id) ?? []} />
+                  {(p.status === "completed" || p.status === "failed") && (
+                    <PhaseSummaryCard missionId={mission.id} phaseId={p.id} />
+                  )}
                   {mission.status === "running" || mission.status === "completed" ? (
                     <div style={{ display: "flex", gap: 6, marginTop: 6 }}>
                       {p.status === "failed" && mission.status === "running" && (