feat: migrate frontend to Astro + expand AI moderation + backend admin/runtime config

Frontend:
- migrate from Vite to Astro (astro.config.mjs, pages/, layouts/)
- add admin panel, settings page, command palette, error boundary
- refactor App.tsx, MascotChatbot, Sidebar, Header, DashboardLayout
- update API client, WebSocket, auth, dashboard features

Backend:
- add admin module and config routes
- refactor middlewares, Redis connection, WebSocket server/bridge
- add runtime config loader

Discord Gateway:
- refactor AI moderation: circuit breaker, concurrency limiter, fallback processor
- add media analysis client, Seaxng search, user profile learner
- add new drizzle migration

Shared:
- extend database schema, add new config fields

services/backend/src/shared/redis/index.ts

@@ -77,6 +77,7 @@ export async function publishCommand<T = unknown>(
     const timer = setTimeout(() => {
       if (settled) return;
       settled = true;
+      sub.removeListener("message", onMessage);
       sub.unsubscribe(replyChannel).catch(() => {
         /* ignore */
       });
@@ -90,6 +91,7 @@ export async function publishCommand<T = unknown>(
       if (channel !== replyChannel || settled) return;
       settled = true;
       clearTimeout(timer);
+      sub.removeListener("message", onMessage);
       sub.unsubscribe(replyChannel).catch(() => {
         /* ignore */
       });
@@ -121,6 +123,7 @@ export async function publishCommand<T = unknown>(
             if (!settled) {
               settled = true;
               clearTimeout(timer);
+              sub.removeListener("message", onMessage);
               sub.unsubscribe(replyChannel).catch(() => {
                 /* ignore */
               });
@@ -133,6 +136,7 @@ export async function publishCommand<T = unknown>(
         if (!settled) {
           settled = true;
           clearTimeout(timer);
+          sub.removeListener("message", onMessage);
           logger.error({ err }, "Failed to subscribe to reply channel");
           resolve(null);
         }