Implement Language Copy and Creation Flow

[oidacra]

Parent Issue

30371

Task

Implement the workflow for creating new language versions:

• If you click a missing locale without content translation, add a confirmation dialog for new language version creation
• Implement content copying from default language
• Setup form population with copied content
• Handle save operation for new contentlet with the new language version

Old DOJO implementation

Acceptance Criteria

• User is prompted when selecting an unavailable language
• Content is correctly copied from default language
• Form is properly populated with copied content
• New language version is saved correctly

Proposed Objective

Same as Parent Issue

Proposed Priority

Same as Parent Issue

[oidacra]

Pending design @dsilvam @melissarojas-dotcms