feat(hub): add org project explorer admin APIs

Expose folder/project tree, create/move/rename/archive, and Feishu
binding archive under /api/org/:orgSlug for OWNER/ADMIN sessions.

hub/src/admin/routes/orgRoutes.ts

@@ -9,6 +9,7 @@ import {
   ensureOrganizationProjectSettings,
   setMembersCanCreateProjects,
 } from "../../projectOnboarding.js";
+import { registerExplorerRoutes } from "./explorerRoutes.js";
 
 export interface OrgRouteConfig {
   readonly prisma: PrismaClient;
@@ -74,4 +75,10 @@ export async function registerOrgRoutes(app: FastifyInstance, config: OrgRouteCo
       return handleRouteError(reply, err);
     }
   });
+
+  await registerExplorerRoutes(app, {
+    prisma: config.prisma,
+    sessionSecret: config.sessionSecret,
+    projectWorkspaceRoot: config.projectWorkspaceRoot,
+  });
 }