fix(provenance): align file matching and report withheld attachments

[icecrasher321]

Summary

• Keep Agent and Copilot turns running when file-provenance checks withhold an attachment. Add a shared model-visible attachment-error notice so answers account for unavailable input without exposing the withheld file's bytes or metadata.
• Apply the shared literal policy before expanding JSON-escaped scan values. Short compiled values cannot acquire protected provenance through escaping, and successfully decrypted short mounted values cannot taint derived binary exports.
• Preserve protection for literals of eight or more characters, unreadable provenance, and binary exports with protected secrets in scope. Keep feature flags and legacy compatibility unchanged.

Type of Change

• Bug fix

Testing

• Bun 1.4.1: 767 focused tests covering shared matching, mounted and compiled output classification, durable-file admission, and Agent/Copilot continuation. New deterministic regressions reproduce both short-literal classification failures before the fix.
• 14 integration tests with disposable PostgreSQL, Redis, and local file storage covering external downloads, archive copies, and model admission.
• App type-check, repository lint, all 46 audits (including API validation), block-registry check, and generated-artifact checks.

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

1 Skipped Deployment

Project	Deployment	Actions	Updated
docs	Skipped		Sep 16, 2026 12:01am UTC

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge and consistently fails before model execution when requested attachments cannot pass provenance admission.

Summary

The PR replaces silent omission of provenance-refused model attachments with explicit request failure across Agent, Copilot, and provider boundaries.

• Agent-generated documents now fail before provider execution when an embedded contributor is not model-safe.
• Copilot validates both supported initial attachment fields without mutating the caller’s payload.
• The shared provider boundary refuses mixed safe/unsafe attachment sets before upload or provider processing.
• Focused tests cover safe and unsafe generated documents, both Copilot attachment aliases, mixed sets, and streaming and non-streaming provider requests.

Diagram

%%{init: {'theme': 'neutral'}}%%
flowchart LR
  A[Agent or Copilot request] --> B[Collect model attachments]
  B --> C[Import durable provenance]
  C --> D{All attachments model-safe?}
  D -->|Yes| E[Hydrate or upload attachments]
  E --> F[Execute provider request]
  D -->|No| G[Fail request explicitly]

Loading

_{Reviews (1) · Last reviewed commit: "fix(provenance): stop silently dropping ..."}

[cubic-dev-ai]

No issues found across 6 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

_{Re-trigger cubic}