Reconcile or retire the legacy milestone sync after the reset

Outcome

Milestone management in this repository matches the reset's module-milestone structure, or is retired. A dispatch of the "Sync GitHub milestones" workflow cannot create or rewrite milestones that contradict the L01-L14 program.

Parent and boundary

Parent: #108 (G00 - Reset repository governance and provenance). Repository governance; no product behavior change.

Grounding

• docs/github-milestones/manifest.json names the retired Notion Loop Roadmap (38f9cb07-9ddb-804a-96db-e26b8d86e84f) as its source and still describes the pre-reset 0.x release train: 0.5.0 is bound to GitHub milestone #12, which is now the live L12 - Automation Runtime, and 0.6.0 is marked "pending creation during sync".
• .github/workflows/sync-milestones.yml is a workflow_dispatch job with issues: write that runs scripts/github/sync_milestones.py --apply; the script creates any manifest title missing remotely, so a dispatch today would create the retired 0.0.1-0.8.0 milestone titles beside the module milestones.
• The manifest and its README landed 2026-09-23, before the reset renamed the repository and replaced release-train milestones with module milestones; the README still calls the retired Roadmap canonical.

Acceptance

• One recorded decision: update the manifest to the current milestone structure and keep the workflow, or retire the directory and workflow explicitly.
• python scripts/github/sync_milestones.py (the default dry run) against the current repository is a no-op, or its planned creates/updates match the recorded structure exactly.
• Failure case: a dispatch of the workflow must not create, close, or rewrite any milestone outside the recorded structure.

Required proof

The dry-run output at the exact head and the decision record. Run the repository's mapped proof and check-change gate for a PR with an internal changelog fragment.

Handoff

Record changed files, observed result, remaining risk, and a 1-3 sentence anti-slop review. Completion means acceptance evidence, not merely a merged implementation.

Sources

Approved master roadmap §2 and §6.1 and the G00 exit gate. Gap review of the issue suite and reset repository state, 2026-10-04.

G00 implementation record, 2026-10-10

PR #262 implements the retirement decision. The dispatch workflow and active manifest are removed. Default dry run is an offline no-op; --apply fails with exit 2 before any external command. The hosted workflow is disabled_manually, preventing dispatch while source removal proceeds through normal promotion after this PR merges into dev. No remote milestone changes were made.

Implementation head: 78f9c0bce909bca7f95cc5b6c701043e61332087. The required check-change gate passed using the existing build with identical plugin ABI inputs. 117 Python cases and the mapped ABI test passed; one optional PdfTool runtime case skipped. Hosted CodeQL checks passed at this head; the native CI build is still running. Full package qualification remains pending. This record does not grant release admission.