chore(ui): remove 4 orphaned views (Dashboard/GenPersona/MySessions/WeakAreas) + mobile polish

- Delete unused views not referenced by router/components (dead files from earlier builds).
- Mobile (640px/460px/380px): nav tabs wrap to a centered full-width row + hide brand at
  <380; logout shows icon-only; stat cards center when collapsing to one column
  (Moreminimore convention); chat bubbles/width handled.
Rebuilt dist.

frontend/dist/assets/users-qxBh6IGP.js

@@ -0,0 +1,6 @@
+import{k as e}from"./index-C0_i8cDF.js";/**
+ * @license lucide-vue-next v1.0.0 - ISC
+ *
+ * This source code is licensed under the ISC license.
+ * See the LICENSE file in the root directory of this source tree.
+ */const r=e("users",[["path",{d:"M16 21v-2a4 4 0 0 0-4-4H6a4 4 0 0 0-4 4v2",key:"1yyitq"}],["path",{d:"M16 3.128a4 4 0 0 1 0 7.744",key:"16gr8j"}],["path",{d:"M22 21v-2a4 4 0 0 0-3-3.87",key:"kshegd"}],["circle",{cx:"9",cy:"7",r:"4",key:"nufk8"}]]);export{r as U};