Raise the serverActions request body limit to 10mb so wiki image uploads
(capped at 8mb in uploadWikiImage) pass through with room for multipart
overhead.
- Add Unsloth OpenAI-compatible provider with @ai-sdk/openai
- Rewrite AI generation handlers with Vercel AI SDK streaming
- Add plainTextToLexicalJson helper for richText field generation
- Configure HeadingFeature and PayloadAiPluginLexicalEditorFeature
- Stub @payloadcms/richtext-lexical server entry in client bundle
- Extract meta constants for site title and description
- Add UNSLOTH_API_KEY to .env.development