Add PCB fabrication review workflow

[Romonaga]

Change Type

• Feature
• Bug fix
• Refactor
• Documentation / workflow artifact
• Repo organization / cleanup
• Other: ___

Linked Workstream Change

• Linked Verlyn change: circuit-shelf-28
• No change applies - reason: ___

Verlyn PR Metadata

Verlyn PR creator: ___

Acceptance Criteria

• Users can review circuit graph findings, KiCad export status, and fabrication package warnings in the UI.
• Gerber download/export requires explicit user acknowledgement of unresolved risks and review status.
• Workflow records review evidence, package manifests, and generation history for traceability.

Verification Runs Completed

• Session baseline
• Architecture check (if configured)
• Workstream validation: python scripts/repo_helpers/workflow/validate.py <id> --strict
• Other:
  • ___

Coverage Summary

• 4 of 4 tracked work items are complete.

AI Assistance Disclosure

• AI-assisted - tool(s) used: Codex
• Human-authored only

Accountable human owner: hellweek

Seeded by Verlyn for Add PCB fabrication review workflow: this tracked change is being managed through Verlyn's solo workflow path. Replace this note with the concrete AI-assisted tools and scope before merge if implementation, review, or packet authoring used AI, or replace it with 'Human-authored only.' when no AI assistance materially shaped the final change.

Independent Cross-Agent Review

• Not required for this change - reason: ___
• Completed - reviewer tool: Verlyn workflow gate | findings summary: No blocking findings recorded.
  • Unresolved findings:
    • ___

Rollback Plan

• Hide/remove fabrication review UI and keep backend generation services inaccessible from normal user workflows.

Handoff Status

• All acceptance criteria satisfied
• Verlyn-managed work items updated
• Outstanding blockers or deferred items noted
• Ready to merge