fix: error handling

- Remove unnecessary try-catch block in createSession function
- Add error handling for missing session ID in socket.js
- Improve error handling in connectDB function
- Add error handling middleware for server errors
- Add default export for get function in env.js

Signed-off-by: wancat <wancat@wancat.cc>

server/src/index.js

@@ -9,6 +9,7 @@ import connectDB from './db.js'
 import apiRouter from './api/routes/index.js'
 import loadAndUpdateQuests from './utils/quest.js'
 import config from './config.js'
+import errorHandler from './middleware/error.js'
 
 async function main() {
   const app = express()
@@ -28,6 +29,8 @@ async function main() {
 
   app.use('/api/v1', apiRouter)
 
+  app.use(errorHandler)
+
   server.listen(config.port, config.host, () => {
     console.log(`Server listening at http://${config.host}:${config.port}`)
   })