refactor(skills): retrofit the corpus to the ADR-0020 context contract (#129)

Retrofits all 39 skills to ADR-0020's description/body context contract, then fixes what six rounds of independent review found in that retrofit — including four ways the hot gate itself failed open.

Closes #99, #107, #108, #110, #111, #114, #115, #120.

## The retrofit (waves 1-5)

| | Start | Now |
|---|---|---|
| Description FAILs (>400 chars) | 26 | **0** |
| Body FAILs (>900 words, body-only) | 9 | **0** |
| Dangling routing targets | 2 | **0** |
| `Kyberforge.CompositionNote` | 10 | **0** |
| Preload tax | 21,005 chars | **~10,500** |

Under the 12,000-char success criterion. Per-wave detail is on #99.

## The review fixes

**The gate failed open four ways, three of them found after the retrofit shipped.** An unrecognised follower token made a dangling target vanish. A skill directory with no `SKILL.md` resolved as a valid target, so a commit could be green locally and red in a fresh clone — three existing fixtures were relying on that, one of which made the install-leak A/B pass vacuously. Then the free-standing `/name` sweep turned out to be gated on the sentence carrying a boundary marker, so route notation in any other sentence was invisible — not an ERROR, not a SUGGESTION, not an INFO — which left the documented "`/name` always blocks" promise false from a second direction. All four fixed and pinned.

**Two checks were silently not running.** `validate-provenance.sh` checks 7-8 were dead across nine skills. Waking them exposed a deeper problem: they assume `Research doc:` names a source index, but 30 of 121 entries point at topic content documents, so every new check-7 INFO was a false positive and check 8 was saved from a false-FAIL flood only by an *unannounced* skip. Checks 7/8 are now scoped to source indexes and every skip announces itself (#121).

**The retrofit's own anti-goal, four times.** ADR-0020 warns that a blunt gate gets satisfied by deleting content rather than relocating it. `diagnose` and `skill-audit` relocated prose and then read it unconditionally; `prototype` and `vale-config` deleted rules outright that survived nowhere. All four addressed.

## Verification

- `bash tests/run-tests.sh --strict` — 24 suites, 0 skipped, 0 failed
- `bash tests/run-bats.sh` — 325 tests, 0 failures
- `pre-commit run --all-files` — 17/17
- `pre-commit run --hook-stage pre-push --all-files` — 16/16, with `apm marketplace check` and `apm pack --check-clean` run against the remote, not skipped
- `scripts/skill-size-check.sh` over all 39 skills — rc 0, 0 ERROR/FAIL, SUGGESTION-only
- Preload tax measured at **10,498 chars**, max description 390 — both inside budget
- Every new test proven non-vacuous by a deliberate mutation of the behaviour it covers

**Per-commit sync, stated accurately:** the ten commits from the latest review round each pass `check-plugin-content-sync` in isolation, verified by checking each out in a detached worktree with a clean between. The earlier gitea window (`dfacf05..bedbd1d`, nine commits) does **not** — its mirror was regenerated in one batch at `bbc7300`. An earlier revision of this description claimed the property held for every commit; it does not, and a bisect through that window lands on a red commit. **Squash-merge** to collapse it, or accept that this range is not bisectable.

## Version bump

Six plugins and the catalog take a **patch**, not a minor. The branch is **89 commits — 40 `fix` / 30 `refactor` / 12 `docs` / 5 `chore` / 2 `test` — zero `feat`, zero `!`, zero `BREAKING CHANGE`** — and adds no skill, agent, command or hook. (Two earlier revisions of this section cited a stale histogram, most recently 78 commits; the figures above are measured at HEAD.) Both rules this repo ships (`forge/references/version-bump.md`, landing in this PR, and `git-commits/references/conventional-commits-spec.md`) make that a patch, and the catalog set is unchanged at 7 entries.

Not settled by that: four published files were removed from the installed tree, three moved, and `caveman` gained `disable-model-invocation`, retiring its old triggers. Under a strict reading those are major-class and currently ship under `refactor:` with no marker. Whether the deployed skill surface is a public contract is written down nowhere — worth deciding, but it outlives this PR.

## Deliberately not in scope

#112 (cherry-pick ownership, now resolved in favour of `git-commits`), #113 (`rtk git` normalisation), #116 (research fan-out), #101 (audit-skill merge), #122 (non-spec skill-root files), #123 (no PRD producer) stay open. #117 is the one worth reading: the contract's remedy is to move prose into `references/`, which is exactly where neither the size gate nor Vale looks — and the blind spot is wider than #117 currently records, since there is no root `.vale.ini` at all, so every ADR, `CONTEXT.md` and `README.md` is unlinted too.

That blind spot let this branch carry two `level: error` `Kyberforge.SentenceOpenerThereIs` violations into `references/` files it created — `provider-adapter-author/references/provider-matrix.md:31` and `agent-audit/references/finding-criteria.md:95`. Both are reworded in `afadaae`, confirmed by routing each file through the audit's own `vale-wrap.sh` (1 error each before, 0 after). Five further occurrences sit in `references/` files already on `main`; those are the pre-existing corpus and stay with #117, which is the real fix.

Also unfixed and not this PR's: `apm install` appends a duplicate `SessionStart` entry to `.claude/settings.json`, so a fresh clone cannot get pre-push green without an edit AGENTS.md warns against. Reproduces identically on `main`.

Co-authored-by: Defame1297 <gitea@rkdr.net>
Reviewed-on: https://git.dev.rkdr.net/Defame1297/holocron/pulls/129
Co-authored-by: Claude Code AI - Gitea MCP <claude@noreply.git.dev.rkdr.net>
Co-committed-by: Claude Code AI - Gitea MCP <claude@noreply.git.dev.rkdr.net>

plugins/gitea/.apm/agents/gitea-orchestrate.agent.md

@@ -23,6 +23,7 @@ You resolve `owner`/`repo` once per session (via `git remote -v` on `origin`) an
 These are non-negotiable regardless of `confirm` or any skill-local override:
 - Never delete the repository's default branch (typically `main` or `master`) — refused outright, independent of `confirm`.
 - `delete_release` takes a numeric `id`; `delete_tag` takes a `tag_name` string. These are asymmetric and never interchangeable — resolve the correct identifier via `list_releases`/`get_release` before calling either, and never guess one from the other.
+- `rename-branch` is gated like a delete even though it destroys nothing: what a rename does to open PRs using the branch as head or base, to a matching protection rule, and to every other clone's tracking branch is unconfirmed by `gitea-branches`' sources. Require `confirm: true`, and verify the PR and protection sides afterwards.
 - Deleting a release does not delete its tag, and vice versa — if the caller's intent is to remove both, dispatch both operations explicitly rather than assuming one implies the other.
 - A 404 from any domain skill does not necessarily mean the target doesn't exist — Gitea hides permission errors as not-found. Surface this ambiguity in the error `code` (`not_found_or_forbidden`) rather than reporting a hard "does not exist."
 - Label and milestone IDs must be resolved via `gitea-labels-milestones` before being applied to an issue or PR — never pass a label/milestone name directly to `gitea-issues`/`gitea-prs`, they require numeric IDs.
@@ -43,7 +44,7 @@ Sub-skills carry their own local copies of relevant gotchas for humans who invok
 
 When invoked, you:
 1. Parse the incoming workflow request (operation type, parameters, context overrides)
-2. Check safety gates: if the operation is destructive (delete-branch, delete-release, delete-tag, delete-label, delete-milestone, delete-file, merge-pr) and the request lacks explicit `confirm: true`, fail immediately with "requires explicit confirmation"; deleting the default branch is refused outright regardless of `confirm`
+2. Check safety gates: if the operation is destructive (rename-branch, delete-branch, delete-release, delete-tag, delete-label, delete-milestone, delete-file, merge-pr) and the request lacks explicit `confirm: true`, fail immediately with "requires explicit confirmation"; deleting the default branch is refused outright regardless of `confirm`
 3. Route to the appropriate domain skill: `gitea-issues`, `gitea-labels-milestones`, `gitea-prs`, `gitea-branches`, `gitea-files`, `gitea-releases`
 4. Manage session context: resolve and carry forward `owner`/`repo` and any cached number-space resolutions, passing them explicitly to each skill
 5. Handle error recovery: for recoverable failures (rate limiting, transient 5xx, pagination gaps) retry or complete the operation; for ambiguous 404s, attempt the permission-vs-not-found disambiguation before failing
@@ -55,12 +56,12 @@ When invoked, you:
   - issues: list-issues, get-issue, create-issue, update-issue, comment-issue, search-issues
   - labels/milestones: list-labels, create-label, update-label, delete-label, list-milestones, create-milestone, update-milestone, close-milestone, delete-milestone, resolve-labels
   - prs: list-prs, get-pr, create-pr, update-pr, close-pr, reopen-pr, merge-pr, review-pr
-  - branches/commits: list-branches, create-branch, delete-branch, list-commits, get-commit
+  - branches/commits: list-branches, create-branch, rename-branch, delete-branch, list-commits, get-commit
   - files: get-file, get-dir, get-tree, write-file, delete-file
   - releases/tags: list-releases, get-release, create-release, delete-release, list-tags, create-tag, delete-tag
 - **parameters:** object, operation-specific arguments (issue/PR number, title, body, label names, tag name, file path, etc.)
 - **context:** object (optional), session state to carry forward (`owner`, `repo`, cached number-space resolutions)
-- **confirm:** boolean (optional), explicit confirmation for destructive operations (required if not set for delete-branch, delete-release, delete-tag, delete-label, delete-milestone, delete-file, merge-pr)
+- **confirm:** boolean (optional), explicit confirmation for destructive operations (required if not set for rename-branch, delete-branch, delete-release, delete-tag, delete-label, delete-milestone, delete-file, merge-pr)
 
 ## Process