docs: suspend CS-RG implementation directives pending revalidation

[novelKR]

Summary

Suspends the CS-RG implementation directives while the owner-directed CS-RG integration-boundary revalidation is pending. Documentation only: it adds status notices and deletes or rewords nothing.

Why

The owner placed the managed-PTY path (CSRG-C00), the runner-owned transport outside the Codex spawn adapter (CSRG-C03) and the legacy-backend convergence (CSRG-C09) on hold and requires a boundary revalidation before any CS-RG implementation. Every later unit depends on CSRG-C00. No separate instruction file points agents at CS-RG work, so these planning documents on main are the live instruction source; this change marks them so that no agent implements from them in the meantime.

What changed

• A status notice under the title of each affected document and under each affected section:
  • docs/planning/milestones/CS-RG.md: the plan, its groups and all ten units
  • docs/design-revision-1.md: the sections that prescribe CodeSpace's target execution architecture, D1, D2, the work-unit changes and the final direction
  • docs/design.md (execution ownership), docs/planning/decisions.md (ADR-006), docs/planning/codespace-integration.md
  • scoped notices in docs/planning/verification.md, docs/planning/consumer-readiness.md, docs/planning/pr-delivery.md and docs/planning/README.md
  • the two 2026-09-27 CS-RG handoffs, whose "start CSRG-C00" steps no longer authorize implementation
• Korean counterparts: the same notices on the matching sections; reviewed hashes recorded with scripts/check_docs.py record.
• AGENTS.md: one bullet stating the suspension. docs/milestones.md: a notice after the milestone table.

What did not change

• No sentence is deleted or reworded; historical text is kept for traceability.
• No new unit, ID, status value or work count (48 units, 25 groups). milestones.json is unchanged: CS-RG not-started / not-run stays accurate, and the ledger has no suspended state to use.
• No replacement architecture is approved; the owner decides after reviewing the revalidation. No safety requirement is relaxed.
• docs/design.ko.md, docs/contracts.md and the qualified release records are unchanged.

Reference review

Inbound references were classified as execution directives, future architecture stated as a current decision, simple links, historical records or implemented facts. The first two received notices; links and history are covered by the document notice; facts are unchanged. Table rows that cite CS-RG units are covered by the section or document notice, since a notice cannot sit inside a table.

Verification

• python3 scripts/check_docs.py: passed (17 reviewed pairs, 48 work units, 25 logical PR groups).
• git diff --check: clean; the diff only adds lines.
• Not run locally: scripts/validate.py (host memory was tight); this PR's CI runs it on macOS and Ubuntu.

Merge and rollback

Merging requires the owner's explicit approval of this exact head. Rollback: revert this commit.

Related

• Review results and session handoff: docs(handoff): record the CS-RG boundary revalidation #13 (docs/handoff/2026-09-27-cs-rg-boundary-revalidation.md). It is a record for the owner's decision, not a design decision.
• CodeSpace counterpart: docs: mark the planned CS-RG managed-execution design as suspended CodeSpace#75.

Handoff (session of 2026-09-27)

• Tracker: Handoff: CS-RG hold, boundary revalidation and pending owner approvals (2026-09-27) #14. Session record: docs(handoff): record the close of the 2026-09-27 session #15 (docs/handoff/2026-09-27-session-close.md). CodeSpace tracker: Handoff: CS-RG managed-execution suspension (#75) and the DevGuard boundary revalidation (2026-09-27) CodeSpace#76; CodeSpace note: docs: record the CS-RG suspension handoff note CodeSpace#77.
• State at handoff: head ae85ebb95b68821361ae59d3c60b5344a1d8ab03, CLEAN, not merged. Merging needs the owner's approval of this exact head (merge track in Handoff: CS-RG hold, boundary revalidation and pending owner approvals (2026-09-27) #14).
• Most urgent of the merge track: until this PR and docs: mark the planned CS-RG managed-execution design as suspended CodeSpace#75 merge, the CS-RG documents on main still read as directives.