feat: implement Telegram multi-channel logging and enhance admin UI/UX guidelines

Telegram Logging Enhancements:
- Support multi-channel notifications (inquiry: -5434691215, system: -5585148480)
- New methods: SendInquiryNotificationAsync, SendSystemNotificationAsync
- Dynamic chat ID routing based on notification type
- Backward compatible with existing default ChatId configuration

Admin UI/UX Improvements (CLAUDE.md 10.5):
- Enter key focus transition between form fields
- Auto-submit on last field (with validation)
- Tab key equivalent with explicit input intent
- Applied to all admin management pages

Dorsum ERP Integration Guide (CLAUDE.md 10.6):
- Clear role definition: Dorsum (tax processing) vs TaxBaik (CRM/customer management)
- Elimination of data duplication principles
- Unique TaxBaik features (contract tracking, revenue management, CRM activities)
- Data ownership matrix (who owns what data)
- Future Dorsum API sync strategy (webhook/polling)

Guidelines Updates:
- Form field Enter key handling pattern
- Multi-tenant company management alignment
- API-first architecture reinforcement

Build Status: ✅ Success (0 errors, 3 warnings)

TaxBaik.Web/appsettings.json

@@ -19,7 +19,9 @@
   },
   "Telegram": {
     "BotToken": "8679990909:AAGLLRUIAuEbYAZVGOYDu-UuTu4ihroEiX0",
-    "ChatId": "-5585148480"
+    "ChatId": "-5585148480",
+    "InquiryChatId": "-5434691215",
+    "SystemChatId": "-5585148480"
   },
   "Admin": {
     "PasswordResetToken": "dev-reset-token-12345"