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-workflow/references/number-resolution.md

@@ -0,0 +1,21 @@
+---
+topic: number-resolution
+source_keys:
+  - gitea-mcp-repo
+  - gitea-mcp-slim-go
+  - context7-websites-gitea
+---
+
+# Resolving a bare issue-or-PR number
+
+The user has referenced a bare number without saying "issue" or "PR" (e.g. "what's going on with #42"). Resolve it with a real call — never dispatch to `gitea-issues` or `gitea-prs` by guessing from phrasing alone, because "that sounds like a bug" is not evidence and the two domains share one number space.
+
+1. Invoke `gitea-issues` to run `issue_read method: "get"` on that number.
+2. Check the response's `is_pull` field:
+   - `true` → it's a PR. Invoke `gitea-prs` for full PR detail (status, diff, reviews as appropriate to the request) and present that instead.
+   - `false` or absent → it's an issue. Present the issue detail already retrieved.
+3. If the resolution call 404s, don't conclude the number doesn't exist. Gitea hides permission errors as not-found (documented in `gitea-issues`' Gotchas), so report the 404 and suggest verifying the token carries `write:issue` rather than reporting "no such issue or PR."
+
+If the user stated an action on the number rather than asking about it, resolution is only step one: hand the action, with the resolved domain, to `gitea-issues` or `gitea-prs` to carry out. Presenting detail is not a substitute for performing the write.
+
+Then report per `SKILL.md`'s Report section, saying which domain the number turned out to be before showing detail ("That's a pull request:" / "That's an issue:") — otherwise the user cannot tell the resolution happened.

plugins/gitea/skills/gitea-workflow/references/skill-index.md

@@ -0,0 +1,22 @@
+---
+topic: skill-index
+source_keys:
+  - gitea-mcp-repo
+---
+
+# Domain-skill index
+
+The request names a capability but not obviously which skill owns it. Find the owner here, then invoke it:
+
+| Skill | Covers |
+|---|---|
+| `gitea-issues` | List/read/create/update issues, comments, search across issues and PRs. Composes `gitea-labels-milestones` for label/milestone resolution. |
+| `gitea-labels-milestones` | Label and milestone CRUD, label inference from conversation context, resolving names/titles to the numeric IDs writes require. Cross-cutting — used by both `gitea-issues` and `gitea-prs`. |
+| `gitea-prs` | List/read/create/update/merge PRs, code reviews. Composes `gitea-labels-milestones` the same way `gitea-issues` does. |
+| `gitea-branches` | Branch list/create/rename/delete, plus commit history (list commits, get a single commit by SHA). |
+| `gitea-files` | Read/write/delete individual files, list a directory, walk the full repo tree. |
+| `gitea-releases` | Release and tag CRUD — draft/prerelease flags, release notes, semver tags. |
+
+A request that already names its own owner (e.g. "create a milestone" → `gitea-labels-milestones`, "read this file from the repo" → `gitea-files`) never needed this index — invoke that skill directly rather than routing through here.
+
+Then report per `SKILL.md`'s Report section: name the skill and hand off — don't duplicate its output format, let it report.

plugins/gitea/skills/gitea-workflow/references/sources.md

@@ -3,9 +3,9 @@
 ## gitea-mcp-repo
 
 - **URL:** https://gitea.com/gitea/gitea-mcp
-- **Description:** Official gitea-mcp repository (v1.3.0) — `operation/*.go` source files documenting all 55 MCP tools. This skill's status view relies on `list_issues`/`list_pull_requests` semantics (via `gitea-issues`/`gitea-prs`), and its ambiguous-number resolution relies on `issue_read`'s `is_pull` field, both verified against this source at authoring time.
+- **Description:** Official gitea-mcp repository (v1.3.0) — `operation/*.go` source files documenting all 55 MCP tools. This skill's status view relies on `list_issues`/`list_pull_requests` semantics (via `gitea-issues`/`gitea-prs`), its ambiguous-number resolution relies on `issue_read`'s `is_pull` field, and its domain-skill index groups that tool surface by owning skill — all verified against this source at authoring time.
 - **Research doc:** plugins/gitea/docs/research/docs/gitea/sources.md
-- **Contributing files:** SKILL.md
+- **Contributing files:** references/status-checkin.md, references/number-resolution.md, references/skill-index.md
 - **Status:** `extracted`
 
 ## gitea-mcp-slim-go
@@ -13,7 +13,7 @@
 - **URL:** https://gitea.com/gitea/gitea-mcp/raw/branch/main/operation/issue/slim.go
 - **Description:** Slim response shape structs from gitea-mcp source — confirms `is_pull` is present on a single-item `issue_read` response, the field this skill's resolution step depends on to distinguish an issue from a PR sharing the same number.
 - **Research doc:** plugins/gitea/docs/research/docs/gitea/sources.md
-- **Contributing files:** SKILL.md
+- **Contributing files:** references/number-resolution.md
 - **Status:** `extracted`
 
 ## context7-websites-gitea
@@ -21,7 +21,7 @@
 - **URL:** context7:/websites/gitea
 - **Description:** Official Gitea docs mirror on Context7 — confirms issues and pull requests share a single per-repository number sequence, and that Gitea returns 404 for permission failures rather than a distinct 403, both facts this skill's resolution and error-handling steps depend on.
 - **Research doc:** plugins/gitea/docs/research/docs/gitea/sources.md
-- **Contributing files:** SKILL.md
+- **Contributing files:** references/number-resolution.md
 - **Status:** `extracted`
 
 ## context7-gitea-tea-cli

plugins/gitea/skills/gitea-workflow/references/status-checkin.md

@@ -0,0 +1,15 @@
+---
+topic: status-checkin
+source_keys:
+  - gitea-mcp-repo
+---
+
+# Status check-in (invoked with no request)
+
+Give a repo status check-in:
+
+1. Invoke `gitea-issues` to list open issues (`state: "open"`).
+2. Invoke `gitea-prs` to list open PRs (`state: "open"`). Run this alongside step 1 — the two are independent reads, so serialising them only adds latency.
+3. Report as two sections, "Open Issues" and "Open Pull Requests", each a compact list of number and title.
+
+Then report per `SKILL.md`'s Report section.