Add outreach rejection reasons tab

tests/web/outreach-route.test.ts

@@ -32,7 +32,7 @@ describe('outreach route', () => {
         byStatus: { discovered: 2, screening: 1, ready: 1, sending: 1, retryable: 1, sent: 2, rejected: 1 },
         ready: 1,
         oldestReadyAt: 2_000,
-        rejectionReasons: [],
+        rejectionReasons: [{ reason: 'Seller signals detected', count: 1 }],
       })),
       getOldestActiveAt: vi.fn(() => 1_000),
       listActive: vi.fn(() => [{
@@ -88,6 +88,7 @@ describe('outreach route', () => {
       activeCount: 6,
       stages: { discovered: 2, screening: 1, ready: 1, sending: 1, retryable: 1 },
       outcomes: { sent: 2, rejected: 1 },
+      rejectionReasons: [{ reason: 'Seller signals detected', count: 1 }],
       candidates: [{
         postId: 'post-1', status: 'sending', hasPreparedMessage: true,
         postUrl: 'https://www.reddit.com/r/example/comments/post-1/hello/',