feat: enhance duty information handling with contact details and current duty view

- Added `bot_username` to settings for dynamic retrieval of the bot's username.
- Implemented `_resolve_bot_username` function to fetch the bot's username if not set, improving user experience in group chats.
- Updated `DutyWithUser` schema to include optional `phone` and `username` fields for enhanced duty information.
- Enhanced API responses to include contact details for users, ensuring better communication.
- Introduced a new current duty view in the web app, displaying active duty information along with contact options.
- Updated CSS styles for better presentation of contact information in duty cards.
- Added unit tests to verify the inclusion of contact details in API responses and the functionality of the current duty view.

webapp/index.html

@@ -24,8 +24,18 @@
     <div class="loading" id="loading"><span class="loading__spinner" aria-hidden="true"></span><span class="loading__text"></span></div>
     <div class="error" id="error" hidden></div>
     <div class="access-denied" id="accessDenied" hidden></div>
+    <div id="currentDutyView" class="current-duty-view hidden"></div>
   </div>
   <script src="https://telegram.org/js/telegram-web-app.js"></script>
-  <script type="module" src="js/main.js"></script>
+  <script type="importmap">
+  {
+    "scopes": {
+      "./js/": {
+        "./js/i18n.js": "./js/i18n.js?v=1"
+      }
+    }
+  }
+  </script>
+  <script type="module" src="js/main.js?v=4"></script>
 </body>
 </html>