fix(kyberforge): bridge apm content to Claude Code's flat plugin discovery

Claude Code's (and Copilot's) native plugin installer has zero awareness of
.apm/ nesting -- it convention-scans only flat skills/, agents/, commands/,
hooks.json at each plugin's root. Confirmed via strings on the installed
claude binary and live installs of git@holocron/gitea@holocron/kyberforge@
holocron, all reporting Skills(0) Agents(0) Hooks(0) post ADR-0015's apm
conversion. Root cause (apm_cli/core/plugin_manifest.py): apm's plugin.json
compiler deliberately strips skills/agents/commands keys, assuming the host
already auto-discovers those convention directories -- it has no model of
.apm/ being host-visible at all. Separately, apm's own bundle exporter
(apm_cli/bundle/plugin_exporter.py, behind `apm pack --format plugin`)
implements the correct .apm/ -> flat mapping, but only ever targeted
build/<name>-<version>/, a path nothing in marketplace.json's source: points
at.

scripts/sync-plugin-content.sh wraps that bundle exporter and copies its
agents/, skills/, commands/, instructions/, extensions/, and merged
hooks.json back into each plugin's own root as a second tracked
compiled-output category -- same governance status as
.claude-plugin/plugin.json: generated from .apm/, never hand-edited. tests/
subdirectories are excluded from the mirror (dev fixtures, not host-visible
runtime content; several hardcode a relative repo-root walk-up sized for the
.apm/-nested depth, which breaks when duplicated one level shallower).
Applied for real across all 6 plugins and verified two ways: `claude plugin
validate --strict` passes on every real plugin directory, and a live
`claude --plugin-dir <path> -p "list skills/agents"` behavioral test
confirms content is now actually discovered.

Also, from the same issue #90 review round:
- scripts/check-manifests.sh pointed at each plugin's root-level plugin.json
  (checking skills/hooks/mcpServers/agents pointer fields) -- that file was a
  stale near-duplicate of .claude-plugin/plugin.json nothing else read or
  wrote, now deleted across all 6 plugins. check-manifests.sh is rewritten to
  validate .claude-plugin/plugin.json instead, and drops the pointer-field
  checks entirely (nothing to check -- those fields are correctly absent by
  design). Content-presence drift is now check-plugin-content-sync's job, a
  new pre-push hook wired in .pre-commit-config.yaml.

docs/adr/0017 records the root cause and decision in full, including two
rejected alternatives (patching plugin.json's path fields directly -- apm's
compiler strips them on every run; pointing marketplace.json at apm pack's
build/ output -- a version-suffixed non-source directory nothing can install
from without an extra build step). ADR-0015 and CONTEXT.md are updated to
point at it.

Refs: #90

plugins/lint/skills/vale-config/references/configuration-reference.md

@@ -0,0 +1,78 @@
+---
+topic: configuration-reference
+source_keys:
+  - context7-websites-vale-sh
+---
+
+## Core Settings
+
+| Key | Type | Purpose |
+|---|---|---|
+| `StylesPath` | string | Path to all Vale-related resources (styles, dictionaries, vocab). |
+| `Packages` | string[] | Packages to download and install via `vale sync`. |
+| `Vocab` | string[] | Vocabularies to load. |
+| `MinAlertLevel` | enum | Minimum severity to report: `suggestion`, `warning`, or `error`. |
+| `IgnoredScopes` | enum | Inline-level HTML tags to ignore. |
+| `SkippedScopes` | enum | Block-level HTML tags to ignore entirely. |
+
+## Format Associations
+
+Map an unrecognized extension onto a supported one so Vale lints it with the right parser — an extension-level substitution only, it does not add new file-type support:
+
+```ini
+[formats]
+mdx = md
+```
+
+## Vocabularies
+
+Reference a named vocabulary (a folder of accept/reject word lists under `StylesPath`) via `Vocab`, then apply styles per glob:
+
+```ini
+StylesPath = styles
+
+Vocab = Blog
+
+[*]
+BasedOnStyles = Vale, MyStyle
+```
+
+## Local Overrides
+
+A project can layer a local `.vale.ini` that overrides `StylesPath`, adds packages, and changes `BasedOnStyles` for a subset of files — local settings merge with or override the global ones:
+
+```ini
+StylesPath = localpath
+
+Packages = write-good
+
+[*.md]
+BasedOnStyles = write-good
+```
+
+## Rule Header Fields
+
+Individual rule YAML files (under a style's directory) support these header fields:
+
+| Field | Required | Default | Purpose |
+|---|---|---|---|
+| `extends` | yes | — | Check this rule extends (e.g. `existence`). |
+| `message` | yes | — | Message shown when triggered; supports `%s` formatting per check type. |
+| `level` | no | `suggestion` | Severity: `suggestion`, `warning`, or `error`. |
+| `scope` | no | `text` | Scope the rule applies to (e.g. `heading`). |
+| `link` | no | — | URL with more info about the rule. |
+| `limit` | no | — | Max number of triggers per file. |
+| `vocab` | no | `true` | Set `false` to disable active vocabularies for this rule. |
+
+## Checks
+
+The underlying functions a rule's `extends` field can reference: `existence`, `substitution`, `occurrence`, `repetition`, `consistency`, `conditional`, `capitalization`, `metric`, `spelling`, `sequence`, `script`.
+
+## Built-in Style
+
+Vale ships with a default `Vale` style containing four rules, usable without `vale sync`:
+
+- `Vale.Spelling` — spell-checks against Hunspell-compatible dictionaries in `<StylesPath>/config/dictionaries`.
+- `Vale.Terms` — enforces the project's accepted vocabulary terms.
+- `Vale.Avoid` — enforces the project's rejected vocabulary terms.
+- `Vale.Repetition` — flags repeated words (e.g. "the the").

plugins/lint/skills/vale-config/references/sources.md

@@ -0,0 +1,9 @@
+# Sources
+
+## context7-websites-vale-sh
+
+- **URL:** context7:/websites/vale_sh
+- **Description:** Official Vale documentation site (vale.sh) indexed by Context7 — `.vale.ini` config reference, style/rule/check model, installation across package managers and Docker.
+- **Research doc:** plugins/lint/docs/research/docs/vale/sources.md
+- **Contributing files:** SKILL.md, references/configuration-reference.md
+- **Status:** `extracted`