UpdateDraftContentInput

Requires project.files.write.

Field	Type	Required	Description
`projectReference`	`String`	No
`entityId`	`ID!`	Yes	Existing source-file path or UUID whose pending full-body draft is replaced.
`entityType`	`DraftEntityType!`	Yes	Must match the existing source-file type.
`branchId`	`ID`	No
`body`	`String!`	Yes	Empty bodies are valid. Saves a durable draft and repairs Yjs state without creating an immutable version.
`branchReference`	`String`	No	Branch name or UUID; equivalent branchId aliases are accepted, conflicting ones rejected. Omit/null for main.
`expectedDraftVersion`	`Int`	No	Expected current draft sequence (0 means no prior draft), not a committed-file version ID. Omit/null for unconditional replacement; stale values are concurrency errors409.