fix: resolve telegram auth token expiration and clean up codebase

- Fix stale initData comparison in clearStaleSessionIfNeeded that destroyed
  valid refresh tokens on mobile WebView reopens
- Restrict X-Telegram-Init-Data header to auth endpoints only
- Close Mini App on auth retry to force fresh initData from Telegram
- Merge Connection page error/not-configured states for better UX
- Remove unnecessary comments across 40+ files (section dividers,
  restating comments, noise catch block comments)
- Configure ESLint allowEmptyCatch to properly handle intentional
  empty catch blocks (62 warnings resolved)

src/api/admin.ts

@@ -147,8 +147,6 @@ export const adminApi = {
   },
 };
 
-// ============ Dashboard Stats Types ============
-
 export interface NodeStatus {
   uuid: string;
   name: string;
@@ -239,8 +237,6 @@ export interface DashboardStats {
   tariff_stats?: TariffStats;
 }
 
-// ============ Extended Stats Types ============
-
 export interface TopReferrerItem {
   user_id: number;
   telegram_id: number | null;
@@ -318,8 +314,6 @@ export interface SystemInfo {
   subscriptions_active: number;
 }
 
-// ============ Dashboard Stats API ============
-
 export const statsApi = {
   // Get system info
   getSystemInfo: async (): Promise<SystemInfo> => {