Sync Application Information with Site Records for Data Consistency

Fixes #15670

Summary

This update ensures that when application information is modified, the corresponding Site records are also updated to maintain data consistency across the system. This fixes the issue where preview URLs show outdated application names after updates.

Changes Implemented

• Enhanced app_service.update_app to sync name, description, and icon settings to Site
• Modified app_service.update_app_name to sync name changes to Site title
• Updated app_service.update_app_icon to sync icon changes to Site
• Added synchronization logic to ensure site records are updated when application details change

Technical Details

• Added event handler for application name updates
• Implemented synchronization between applications and sites tables
• Ensured database commits properly update both tables

Testing

• Verified name updates are reflected in preview URLs
• Tested synchronization with:
  • Application name changes
  • Icon updates
  • Description modifications

Impact

This ensures that users always see the most up-to-date information when:

• Viewing applications through the web interface
• Sharing preview URLs with stakeholders
• Demonstrating applications to management

Related Issue

This PR addresses the synchronization issue detailed in #15670, where application name updates were not being reflected in the preview URLs.

Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods