feat(federation): add POST /api/federation/peers/:id/reset

Admin-only endpoint for recovering from needs_attention. Deletes the
local peer row; FK cascade removes queued outbox entries. Gated to
peers in needs_attention to prevent accidental resets of healthy
peerings (use /peers/:id for revoke on active peers).

Also extends the Task 8.5 test mock of '../db/index.js' to re-export
`schema`. federation.ts imports `schema` from the re-export alongside
`getDb`; the previous mock only exposed `getDb`, causing the route
handler to blow up with 500s before reaching any assertion. This is
a scaffolding fix — no test assertions were changed.

packages/server/src/routes/federation.reset.test.ts

@@ -16,8 +16,10 @@ let currentUserId = 'admin-user';
 let currentUserIsAdmin = true;
 
 // Mock getDb BEFORE importing the route module so the module reads our test DB.
+// Must also re-export `schema` because federation.ts imports it from '../db/index.js'.
 vi.mock('../db/index.js', () => ({
   getDb: () => testDb,
+  schema,
 }));
 
 // Mock the auth middleware to honour test-controlled currentUserId / currentUserIsAdmin.

packages/server/src/routes/federation.ts

@@ -845,6 +845,45 @@ export async function federationRoutes(app: FastifyInstance): Promise<void> {
     },
   );
 
+  // ─── POST /api/federation/peers/:id/reset ──────────────────────────────────
+  // Admin-only: reset a peer that has transitioned to needs_attention.
+  // Deletes the local peer row (cascade-deletes outbox entries via FK).
+  // Admin must re-initiate peering out of band after reset.
+  app.post<{ Params: { id: string } }>(
+    '/api/federation/peers/:id/reset',
+    { preHandler: [authenticate, requireAdmin] },
+    async (request, reply) => {
+      const { id } = request.params;
+      const db = getDb();
+
+      const peer = db
+        .select()
+        .from(schema.federationPeers)
+        .where(eq(schema.federationPeers.id, id))
+        .get();
+
+      if (!peer) {
+        return reply.code(404).send({ error: 'Peer not found', statusCode: 404 });
+      }
+
+      if (peer.status !== 'needs_attention') {
+        return reply.code(400).send({
+          error: 'Reset is only available for peers in the needs_attention state. Use revoke for active peers.',
+          statusCode: 400,
+        });
+      }
+
+      // Cascade-delete handles federation_outbox entries (FK onDelete: 'cascade').
+      db.delete(schema.federationPeers)
+        .where(eq(schema.federationPeers.id, id))
+        .run();
+
+      connectionManager.sendToAdmins({ type: 'federation_peers_changed' as const });
+
+      return reply.code(200).send({ success: true });
+    },
+  );
+
   // ─── PATCH /api/federation/peers/:id ────────────────────────────────────────
   // Admin-only: update peer settings (e.g. auto-rotation interval).
   app.patch<{ Params: { id: string }; Body: { autoRotateIntervalDays?: number } }>(