fix(broker): reload broker after migrate-auth

docs/migration.md

@@ -26,7 +26,7 @@ where the principal is the C2C installation (`c2c_inst_…`).
 To upgrade without deleting legacy files:
 
 ```bash
-c2c broker migrate-auth
+c2c broker migrate-auth — merges legacy per-workspace tokens into the installation store; restarts the broker when running so migrated tokens are recognized immediately.
 ```
 
 This copies live client registrations and unexpired tokens into the

src/cli/index.ts

@@ -1451,6 +1451,16 @@ brokerCmd
         `Migrated ${result.tokensMigrated} token(s) from ${result.sourceFiles.length} legacy file(s) to ${result.installationId}`
       );
       say("Legacy auth files were kept for rollback.");
+      // The running broker holds auth in memory: restart so migrated tokens
+      // are recognized without waiting for the next natural restart.
+      const { stopBroker, ensureBroker } = await import("../broker/daemon.js");
+      const wasRunning = (await import("../broker/daemon.js")).installationRuntime();
+      if (wasRunning) {
+        await stopBroker();
+        await new Promise((resolve) => setTimeout(resolve, 500));
+        await ensureBroker();
+        check("Broker restarted to load the migrated tokens");
+      }
     } catch (error) {
       handleCliError(error, opts.json);
     }