refactor(authority): reconcile retirement checkpoints and target types

[loopx-agent]

Goal And Delivered Outcome

Related to #6396, C1/T4 retirement. Earlier RFC/ledger passages still described live normal Markdown writers as future deletion work while the 2.0 candidate had already removed them. The current frontier now describes the candidate; earlier source-specific evidence is explicitly historical, and adoption/recovery/D2/default exits remain open.

The existing two-value execution-target vocabulary now has one shared ExecutionHandoffMode type, used by reviewed migration targets and the frontend ownership API. Historical HandoffMode and receipt decoding retain legacy. No runtime rule, wire schema, configuration default, UI interaction or tool authority changes.

Author Declaration

Written by: model_agent, OpenAI GPT-6 / Codex. Two DCO-signed commits preserve Duang's parent history.

Implemented against parent 5d29213d3ac9f12d0c61bc509ed296cbdfd149ea, the linked accepted refinement frame, and its existing handoff_mode_vocabulary.ts / C1-T4 RFC boundaries:

Criterion	Disposition	Owning paths / evidence
Current candidate versus historical writer inventory	implemented	English/Chinese TS RFC and retirement ledger; local relative links resolve and historical validation is retained
Two new execution/configuration targets; three historical values	implemented	Existing vocabulary, policy re-export, migration target and frontend API type; both typechecks, erased-JavaScript parity and real CLI policy tests
Source-qualified parent validation summary	companion metadata update	The loopx-project#6396 body is updated separately; this supplement does not relabel its evidence as parent-head validation before adoption

Scope And Continuation

Base: Duang777:codex/remove-legacy-markdown-callers-20261012, exactly 5d29213d3; no unrelated main history. This completes the bounded docs/type refinement. The parent remains an open 2.0 proposal with its existing installed adoption, natural Host, retained recovery and formal D2/D3/default exits. This PR grants no merge/release authority and does not automatically migrate any Goal.

Future-facing pass: consolidate the two repeated type expressions in their existing owner; keep the shared historical storage/policy migration planner broad because it has real retained-format consumers. No new framework, helper layer or language migration is needed.

Validation

• Tested revision: 6683c746e2a18a2d609a1e0152a4360431e4db4d (same source bytes as the precommit runs).
• Run state: finished.
• Input classes: synthetic, public_fixture.

Check kind	Result	Evidence / limitation
static / regression_parity	passed	Control-plane and dashboard typechecks; all four changed TS modules emit identical JavaScript to the parent after type erasure/comments removal
unit / real_backend	passed	Existing handoff_mode_plan.test.ts and local_authority_defaults.test.ts: 22 passed, zero skips, including real File/SQLite target creation
real_entrypoint	passed	Existing new-Goal storage, public handoff-mode CLI and canonical handoff Python files: 93 passed, zero skips; no new test-only abstraction
integration	passed	npm run build in the dashboard: production frontend and Chat bundle built and verified
static	passed	Semantic diff advisory and full-tree drift; local Markdown links, eight-file public boundary scan and diff hygiene clean
risk-based canary	passed	Parent-based canary: three direct plus 19 selected checks passed, zero failures/skips/manual holds for this supplement
change quality	passed	Eight-path exact-scope receipt cqr_855698c4c922e54ec86e verified valid; safe-fix allowed, unused; no blockers/warnings/advisories

No database/store implementation or runtime execution behavior changes; the current type-only delta does not require repeating parent-wide PostgreSQL, sustained-load or full-repository runs. Those earlier qualification boundaries remain source-specific and open where unproven. Remote CI is not claimed as observed or green.

Frontend / Visual Evidence

UI impact: none. The frontend edit only imports the shared type and preserves its public alias; emitted JavaScript is identical. No first-screen, widget, available/error state or user operation changes. CLI/Lark/Host behavior is unchanged; the existing real CLI cases and bundle build qualify this type-only delta, not natural installed use.

Shared-authority RFC Fixture Impact

No new fixture schema, semantic dimension, provider routing, promotion or compatibility projection. Existing three-value historical decoding, two-value fresh targets and all original negative paths remain. Source File/SQLite real paths were rerun; PostgreSQL/legacy replay evidence for the unchanged runtime remains with the parent review.

• Public/private scan clean; no credentials, local paths, raw evidence or private state in the diff.
• Every commit is DCO signed; no force push or contributor-history rewrite.