fix(HEL-243): 当前账号可点击返回，避免切换死路

当前账号行原先只显示对号、不可点击，单账号时只能关网页。现改为整行继续使用且不重新签发会话，并带回切换前的业务页。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

config/architecture-inventory.json

@@ -553,16 +553,16 @@
       "bytes": 13681,
       "lines": 338
     },
+    {
+      "path": "frontend/shared/session.js",
+      "bytes": 13219,
+      "lines": 289
+    },
     {
       "path": "frontend/shared/dashboard.js",
       "bytes": 12894,
       "lines": 274
     },
-    {
-      "path": "frontend/shared/session.js",
-      "bytes": 12848,
-      "lines": 283
-    },
     {
       "path": "backend/features/market/insights_auction_data.py",
       "bytes": 12829,
@@ -673,16 +673,16 @@
       "bytes": 5451,
       "lines": 118
     },
+    {
+      "path": "frontend/pages.config.js",
+      "bytes": 5385,
+      "lines": 130
+    },
     {
       "path": "frontend/pages/market/search.js",
       "bytes": 5384,
       "lines": 131
     },
-    {
-      "path": "frontend/pages.config.js",
-      "bytes": 5380,
-      "lines": 130
-    },
     {
       "path": "frontend/pages/auction/page.html",
       "bytes": 5350,