Implementing Ui Bundle File Upload

You get an upload() function with progress tracking and three patterns: basic upload for just getting a contentBodyId, immediate record linking when you already have a record ID, and deferred linking for create-record-with-attachments flows. The API-only approach means you build your own file inputs and progress bars using the callbacks, which gives you flexibility but requires more UI work upfront. Good fit if you need custom upload UX or multi-step forms where the record doesn't exist yet. Supports cancellation via AbortController and integrates with Salesforce ContentVersion records.