Add required fields to multiple schema overrides

[mailsongabriel]

Summary

• Adds required field arrays to 14 schemas that were missing them
• This fixes an issue where Fern generates all properties as Optional<T> in the Java SDK when schemas don't have required arrays defined

Schemas Updated

Conversation-related:

• conversation_rating: rating, created_at
• conversation_part: type, id, part_type, created_at, updated_at, author, redacted
• conversation_part_author: type, id

Ticket-related:

• ticket_part: type, id, part_type, created_at, updated_at, author, redacted
• ticket_part_author: type, id

Core objects:

• segment: type, id, name, created_at, updated_at, person_type
• team: type, id, name, admin_ids
• conversation_source: type, id, delivered_as, author, redacted
• linked_object: type, id

News/Help Center:

• news_item: type, id, workspace_id, title, state, created_at, updated_at
• newsfeed: type, id, name, created_at, updated_at
• newsfeed_assignment: newsfeed_id
• help_center: id, workspace_id, created_at, updated_at, identifier

Attachments:

• part_attachment: type, name, url

Test plan

• Verify Fern regenerates SDK correctly
• Check generated Java classes have non-Optional fields for the specified required properties
• Run SDK tests to ensure no regressions

🤖 Generated with Claude Code