chore(realtime): remove unused SOCKET_PORT env var

SOCKET_PORT has lived in the socket server since the June 2025 refactor
but was never actually set in any deploy config — docker-compose.prod,
helm values/templates, .env.example, and docs all use PORT or the 3002
default exclusively. No self-hoster was ever pointed at SOCKET_PORT, so
removing it is safe.

Simplifies realtime port resolution to `env.PORT` (zod-validated with a
3002 default) and drops the orphaned sim-side schema entry.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

apps/realtime/src/env.ts

@@ -10,7 +10,6 @@ const EnvSchema = z.object({
   NEXT_PUBLIC_APP_URL: z.string().url(),
   ALLOWED_ORIGINS: z.string().optional(),
   PORT: z.coerce.number().int().positive().default(3002),
-  SOCKET_PORT: z.coerce.number().int().positive().optional(),
   DISABLE_AUTH: z
     .string()
     .optional()

apps/realtime/src/index.ts

@@ -29,7 +29,7 @@ async function createRoomManager(io: SocketIOServer): Promise<IRoomManager> {
 
 async function main() {
   const httpServer = createServer()
-  const PORT = Number(env.SOCKET_PORT ?? env.PORT ?? 3002)
+  const PORT = env.PORT
 
   logger.info('Starting Socket.IO server...', {
     port: PORT,

apps/sim/lib/core/config/env.ts

@@ -248,7 +248,6 @@ export const env = createEnv({
 
     // Real-time Communication
     SOCKET_SERVER_URL:                     z.string().url().optional(),            // WebSocket server URL for real-time features
-    SOCKET_PORT:                           z.number().optional(),                  // Port for WebSocket server
     PORT:                                  z.number().optional(),                  // Main application port
     INTERNAL_API_BASE_URL:                 z.string().optional(),                  // Optional internal base URL for server-side self-calls; must include protocol if set (e.g., http://sim-app.namespace.svc.cluster.local:3000)
     ALLOWED_ORIGINS:                       z.string().optional(),                  // CORS allowed origins