feat: Support multiple concurrent login sessions per platform (#2816)

* Initial plan

* Implement multi-device login support - allow multiple concurrent sessions

Co-authored-by: whyour <22700758+whyour@users.noreply.github.com>

* Address code review feedback - extract constants and utility functions

Co-authored-by: whyour <22700758+whyour@users.noreply.github.com>

* Add validation and logging improvements based on code review

Co-authored-by: whyour <22700758+whyour@users.noreply.github.com>

* Revert unnecessary file changes - keep only multi-device login feature files

Co-authored-by: whyour <22700758+whyour@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: whyour <22700758+whyour@users.noreply.github.com>

back/loaders/express.ts

@@ -9,6 +9,7 @@ import rewrite from 'express-urlrewrite';
 import { errors } from 'celebrate';
 import { serveEnv } from '../config/serverEnv';
 import { IKeyvStore, shareStore } from '../shared/store';
+import { isValidToken } from '../shared/auth';
 import path from 'path';
 
 export default ({ app }: { app: Application }) => {
@@ -77,11 +78,8 @@ export default ({ app }: { app: Application }) => {
     }
 
     const authInfo = await shareStore.getAuthInfo();
-    if (authInfo && headerToken) {
-      const { token = '', tokens = {} } = authInfo;
-      if (headerToken === token || tokens[req.platform] === headerToken) {
-        return next();
-      }
+    if (isValidToken(authInfo, headerToken, req.platform)) {
+      return next();
     }
 
     const errorCode = headerToken ? 'invalid_token' : 'credentials_required';

back/loaders/sock.ts

@@ -4,6 +4,7 @@ import { Container } from 'typedi';
 import SockService from '../services/sock';
 import { getPlatform } from '../config/util';
 import { shareStore } from '../shared/store';
+import { isValidToken } from '../shared/auth';
 
 export default async ({ server }: { server: Server }) => {
   const echo = sockJs.createServer({ prefix: '/api/ws', log: () => {} });
@@ -17,21 +18,19 @@ export default async ({ server }: { server: Server }) => {
     const authInfo = await shareStore.getAuthInfo();
     const platform = getPlatform(conn.headers['user-agent'] || '') || 'desktop';
     const headerToken = conn.url.replace(`${conn.pathname}?token=`, '');
-    if (authInfo) {
-      const { token = '', tokens = {} } = authInfo;
-      if (headerToken === token || tokens[platform] === headerToken) {
-        sockService.addClient(conn);
 
-        conn.on('data', (message) => {
-          conn.write(message);
-        });
+    if (isValidToken(authInfo, headerToken, platform)) {
+      sockService.addClient(conn);
 
-        conn.on('close', function () {
-          sockService.removeClient(conn);
-        });
+      conn.on('data', (message) => {
+        conn.write(message);
+      });
 
-        return;
-      }
+      conn.on('close', function () {
+        sockService.removeClient(conn);
+      });
+
+      return;
     }
 
     conn.close('404');