add confirmation dialog to chat creation

This commit introduces a confirmation dialog before creating a new chat. The dialog displays the final chat title, which is now dynamically generated based on the user's input or the names of the selected participants.

Key changes:
- Added a confirmation dialog that appears when the user clicks the "create chat" button.
- Implemented logic to generate a provisional chat title from participants' names if no title is explicitly set.
- Refactored `CreateChatViewModel` by removing the interface and simplifying the implementation.
- Added new string resources for the confirmation dialog.

core/ui/src/main/res/values-ru/strings.xml

@@ -286,4 +286,7 @@
     <string name="week_short">Н</string>
     <string name="day_short">Д</string>
     <string name="time_now">Сейчас</string>
+
+    <string name="confirm_chat_create_with_title">Вы действительно хотите создать чат «%s»?</string>
+    <string name="confirm_chat_create_empty_with_title">Вы действительно хотите создать чат «%s» только с собой?</string>
 </resources>

core/ui/src/main/res/values/strings.xml

@@ -363,4 +363,7 @@
     <string name="week_short">W</string>
     <string name="day_short">D</string>
     <string name="time_now">Now</string>
+
+    <string name="confirm_chat_create_with_title">Are you sure you want to create chat «%s»?</string>
+    <string name="confirm_chat_create_empty_with_title">Are you sure you want to create chat «%s» only with yourself?</string>
 </resources>