The context id assigned to this file at staging.
OptionalerrorMachine-readable class of a failed file, for outcomes to treat differently from real failures.
'DUPLICATE_CONTENT' marks a duplicate found by the deferred extraction pass (a presigned
object's bytes are first read there) — a skip, not a failure: the KB already holds this content.
Additive; absent for ordinary failures.
OptionalerrorPresent only when status is 'failed': the terminal failure reason.
User-facing per-file status.
The file's title — the uploaded file name, or the caller-supplied title for text contexts.
Per-file/per-context status within a bulk-ingestion job, so a caller can see which file finished, which is still processing, and why a file failed.