Enhance calm-day Patrol empty state with coverage context

When the latest Patrol run is available, the healthy empty state body
now includes the coverage summary (e.g. 'Checked 42 resources.') as a
prefix, giving the user immediate freshness and coverage context on a
calm day instead of just 'no action needed'. Addresses checklist L51-53.

frontend-modern/src/utils/__tests__/patrolEmptyStatePresentation.test.ts

@@ -89,7 +89,7 @@ describe('patrolEmptyStatePresentation', () => {
             status: 'error',
             error_count: 1,
             resources_checked: 72,
-          } as PatrolRunRecord,
+        } as unknown as PatrolRunRecord,
         ],
       }),
     ).toEqual({
@@ -241,4 +241,51 @@ describe('patrolEmptyStatePresentation', () => {
       tone: 'warning',
     });
   });
+
+  it('includes latest-run coverage context in the healthy empty state body', () => {
+    const result = getPatrolFindingsEmptyState({
+      filter: 'active',
+      overallHealth: {
+        score: 100,
+        grade: 'A',
+        trend: 'stable',
+        factors: [],
+        prediction: 'Infrastructure is healthy with no significant issues detected.',
+      },
+      runtimeState: 'active',
+      runs: [
+        {
+          id: 'run-1',
+          started_at: '2026-06-27T10:00:00Z',
+          status: 'no_issues',
+          error_count: 0,
+          resources_checked: 42,
+          scope_resource_ids: [],
+          effective_scope_resource_ids: [],
+          finding_ids: [],
+        } as unknown as PatrolRunRecord,
+      ],
+    });
+    expect(result.title).toBe('No current issues');
+    expect(result.body).toContain('Checked 42 resources');
+    expect(result.body).toContain('No action needed');
+    expect(result.tone).toBe('success');
+  });
+
+  it('omits coverage context when no runs are available', () => {
+    const result = getPatrolFindingsEmptyState({
+      filter: 'active',
+      overallHealth: {
+        score: 100,
+        grade: 'A',
+        trend: 'stable',
+        factors: [],
+        prediction: 'Infrastructure is healthy with no significant issues detected.',
+      },
+      runtimeState: 'active',
+    });
+    expect(result.body).toBe(
+      'No action needed from the latest Patrol check. Run Patrol any time to check again.',
+    );
+  });
 });

frontend-modern/src/utils/patrolEmptyStatePresentation.ts

@@ -142,6 +142,20 @@ function hasHistoricalRegressions(count: number | undefined): boolean {
   return typeof count === 'number' && Number.isFinite(count) && count > 0;
 }
 
+function getLatestRunCoverageContext(
+  runs: PatrolRunRecord[] | undefined,
+): string | undefined {
+  if (!runs || runs.length === 0) {
+    return undefined;
+  }
+  const latestRun = runs[0];
+  const coverageSummary = getPatrolRunCoverageSummary(latestRun);
+  if (!coverageSummary) {
+    return undefined;
+  }
+  return `${coverageSummary}.`;
+}
+
 function getPatrolRunSnapshotEmptyState(
   run: PatrolRunSnapshotEmptyStateArgs,
 ): PatrolFindingsEmptyStateCopy {
@@ -237,9 +251,12 @@ export function getPatrolFindingsEmptyState(args: {
     };
   }
 
+  const coverageContext = getLatestRunCoverageContext(args.runs);
   return {
     title: PATROL_QUEUE_CLEAR_TITLE,
-    body: HEALTHY_PATROL_EMPTY_STATE_BODY,
+    body: coverageContext
+      ? `${coverageContext} ${HEALTHY_PATROL_EMPTY_STATE_BODY}`
+      : HEALTHY_PATROL_EMPTY_STATE_BODY,
     tone: 'success',
   };
 }