feat(licenses): add POST /licenses/revoke endpoint

Sets license status to 'revoked' and clears all device activations.
Returns the updated license doc. Idempotent — already-revoked licenses
return immediately.

services/platform-service/src/modules/licenses/routes.ts

@@ -177,6 +177,23 @@ export async function licenseRoutes(app: FastifyInstance) {
     return updated;
   });
 
+  // Revoke license
+  app.post('/licenses/revoke', async req => {
+    const { key } = req.body as { key: string };
+    if (!key) throw new BadRequestError('key is required');
+    const productId = getRequestProductId(req);
+    const license = await repo.getByKey(key, productId);
+    if (!license) throw new NotFoundError('License not found');
+    if (license.status === 'revoked') return license;
+
+    const updated = await repo.update(license.id, license.userId, {
+      status: 'revoked',
+      deviceIds: [],
+    });
+    if (!updated) throw new NotFoundError('License update failed');
+    return updated;
+  });
+
   // Status
   app.get('/licenses/status/:key', async req => {
     const { key } = req.params as { key: string };