fix: recover CMPP slots after gateway restart

api/src/sms-config/sms-config.service.spec.ts

@@ -541,6 +541,9 @@ describe('SmsConfigService', () => {
         remoteIp: '127.0.0.1',
       }),
     });
+    expect(prisma.cmppDownstreamConnection.deleteMany).toHaveBeenCalledWith({
+      where: { status: 'connected', lastHeartbeatAt: { lt: new Date('2026-07-11T10:58:30.000Z') } },
+    });
     expect(prisma.operationLog.create).toHaveBeenCalledWith({
       data: expect.objectContaining({
         action: 'cmpp_downstream_connection.connected',

api/src/sms-config/sms-config.service.ts

@@ -681,6 +681,10 @@ export class SmsConfigService {
     if (data.remoteIp && !isIpAllowed(data.remoteIp, application.ipAllowlist.map((item) => item.ipCidr))) {
       throw new ForbiddenException('CMPP source IP is not in application allowlist');
     }
+    // A Gateway process can disappear before it reports disconnect. Prune its
+    // expired rows here so a restarted process can reclaim connection slots
+    // without waiting for an operator to open the connection-list page.
+    await this.markTimedOutDownstreamConnections(observedAt);
     const activeConnections = await this.prisma.cmppDownstreamConnection.findMany({
       where: { applicationId: application.id, status: 'connected' },
       select: { connectionId: true },