Upload a file chunk

Upload a single chunk of a file within an active upload session.

Send raw binary data in the request body with Content-Type: application/octet-stream. No size limit is enforced — the chunk size is determined by the session’s chunkSizeBytes.

Chunk index: Zero-based. Send chunks in ascending order: 0, 1, 2, …

Single-chunk shortcut: If totalChunks == 1, send the entire file as chunk 0.

Idempotent: Re-sending an already-received chunk is a no-op.

Last chunk behavior: The final chunk (when all files are fully uploaded) automatically:

1. Commits all staged blocks to Azure Blob Storage
2. Triggers the compliance analysis pipeline
3. Returns isComplete: true with documentId, complianceReviewId, and status

Status codes:

• 200 OK - Chunk received (intermediate chunks return isComplete: false)
• 400 Bad Request - sessionId or fileId is not a valid ULID
• 404 Not Found - Session or file not found
• 410 Gone - Session has expired

After completion: Poll GET /v1/documents/{documentId}/status for processing progress, then retrieve results via GET /v1/documents/{documentId}/result.