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/skills/gitea-branches/SKILL.md

@@ -2,37 +2,30 @@
 name: gitea-branches
 
 description: >
-  Use when managing Gitea repository branches — listing, creating, or deleting
-  branches — or inspecting commit history within a Gitea repo: listing commits
-  (optionally filtered by branch or file path) or getting full detail for a
-  single commit by SHA. Triggers on "list branches", "create a branch",
-  "delete a branch", "what commits are on this branch", "show commit <sha>",
-  "what changed in that commit" — even if the user doesn't say "Gitea"
-  explicitly, as long as the repo's remote is a Gitea instance. Do not use for
-  local git branch/commit operations on your working copy (use git-branches or
-  git-history) or for PR-side branch references like cross-repo fork PR heads
-  (use gitea-prs).
+  Use when listing, creating, renaming, or deleting branches in a Gitea repository,
+  or reading its commit history — "what commits are on this branch", "what changed
+  in that commit" — even when the user does not say "Gitea". Not a
+  local checkout's branches -> `git-branches`. Not local history ->
+  `git-history`. Not a PR's head or base -> `gitea-prs`.
 
-compatibility: Requires Gitea MCP server configured with a token with write:repository scope; this is confirmed to gate list_branches, create_branch, and delete_branch (Gitea gates reads behind write scope for repo-scoped operations), and is inferred by analogy (not explicitly confirmed by source docs) to also gate list_commits and get_commit. Requires git remote "origin" pointing to the Gitea instance.
+compatibility: Requires Gitea MCP server configured with a token with write:repository scope; this is confirmed to gate list_branches, create_branch, and delete_branch (Gitea gates reads behind write scope for repo-scoped operations), and is inferred by analogy (not explicitly confirmed by source docs) to also gate rename_branch, list_commits, and get_commit. Requires git remote "origin" pointing to the Gitea instance.
 
 metadata:
   category: integration
-  version: "0.1.1"
+  version: "0.1.2"
   source_keys:
     - gitea-mcp-repo
     - gitea-mcp-slim-go
     - context7-websites-gitea
 
-allowed-tools: Bash mcp__gitea__list_branches mcp__gitea__create_branch mcp__gitea__delete_branch mcp__gitea__list_commits mcp__gitea__get_commit
+allowed-tools: Bash mcp__gitea__list_branches mcp__gitea__create_branch mcp__gitea__rename_branch mcp__gitea__delete_branch mcp__gitea__list_commits mcp__gitea__get_commit
 ---
 
 ## Gotchas
 
-- **Never delete a protected branch (`main`/`master` by name, or `protected: true` from `list_branches`) without explicit confirmation.** `delete_branch` is a direct API call, not a local `git push` — there is no client-side force-push guard protecting it. Name-matching `main`/`master` is a convenient default but not authoritative — a repo can protect a differently-named default branch. When in doubt, call `list_branches` first and check `protected` on the target; treat deletion of any protected branch as a hard refusal unless the user explicitly confirms in the conversation.
-- **404 may actually mean 403.** Gitea hides permission errors as not-found to avoid leaking resource existence. If any of these five tools returns 404 unexpectedly, check token scope (see `references/branches.md` / `references/commits.md`) before concluding the branch or commit doesn't exist.
-- **Pagination is manual.** `list_branches` and `list_commits` return one page at a time — no auto-pagination in the MCP layer. When you need a complete list, iterate `page: 1, 2, ...` until the returned count is less than `per_page`.
-- **Owner/repo always come from the git remote, never from `get_me`.** Resolve them via `git remote get-url origin` (Step 1 below). `get_me`/`list_my_repos` are blocked under the token scopes this skill assumes.
-- **`create_branch`'s source is `old_branch`, not "wherever gitea-mcp feels like."** Omitting `old_branch` forks from the repo's server-side default branch — not necessarily the branch you're currently working on locally. If you want to branch from your current checkout, pass `old_branch` explicitly.
+- **404 often means 403.** Gitea masks permission errors as not-found; on an unexpected one, check token scope before reporting a branch or commit missing.
+- **Nothing auto-paginates.** `list_branches` and `list_commits` return one page; iterate `page` until the returned count is below `per_page`.
+- **`delete_branch` has no force-push guard.** Treat deleting a protected branch as a hard refusal unless the user explicitly confirms it in the conversation. Check `protected` from `list_branches` first — a protected branch need not be named `main`.
 
 ## Step 1 — Resolve owner and repo
 
@@ -42,7 +35,7 @@ Before any tool call, extract `owner` and `repo` from the git remote:
 git remote get-url origin
 ```
 
-If origin is not set or the URL is not a Gitea URL, stop and report: "No Gitea remote found — set origin to your Gitea instance URL."
+`get_me` and `list_my_repos` are blocked under the token scope this skill assumes, so the remote is the only source. If origin is not set or the URL is not a Gitea URL, stop and report: "No Gitea remote found — set origin to your Gitea instance URL."
 
 ## Step 2 — Dispatch
 
@@ -50,17 +43,18 @@ If origin is not set or the URL is not a Gitea URL, stop and report: "No Gitea r
 |---|---|
 | `/gitea-branches` or `/gitea-branches list` | List branches |
 | `/gitea-branches create <name> [from <base>]` | Create branch |
+| `/gitea-branches rename <name> to <new-name>` | Rename branch |
 | `/gitea-branches delete <name>` | Delete branch |
 | `/gitea-branches commits [on <branch>] [touching <path>]` | List commit history |
 | `/gitea-branches commit <sha>` | Get full detail for one commit |
 
-For branch operations (list/create/delete), read `references/branches.md`.
+For branch operations (list/create/rename/delete), read `references/branches.md` — it carries the call signatures, the `old_branch` source rule, and the protected-branch refusal in full.
 For commit operations (list/get), read `references/commits.md`.
 
 ## Step 3 — Report
 
 For reads: display branches as name + protected flag; display commits as SHA (short), message summary, author, date.
 
-For writes (create/delete): confirm the action taken, the branch name, and (for create) the base it forked from.
+For writes (create/rename/delete): confirm the action taken, the branch name, and (for create) the base it forked from or (for rename) the name it had before.
 
-For errors: surface the HTTP code and message. If a 404 is unexpected, re-check token scope per the Gotchas above before reporting "not found" to the user.
+For errors: surface the HTTP code and message, applying the 404 gotcha above before reporting "not found" to the user.