build(apm): consume holocron plugins through apm instead of plugin install

Why:
The repo published apm packages but consumed them the old way — `claude plugin install
<name>@holocron`, six plugins enabled per project. Dogfooding stopped one layer short of the
install tooling kyberforge itself ships.

Implementation notes:
- Root apm.yml declares the six packages as dependencies.apm git+path objects against the
  holocron remote. Object form over `<name>@holocron` aliases on purpose: an alias first needs
  `apm marketplace add`, which writes to ~/.apm/marketplaces.json — user scope, absent on a fresh
  clone. Unpinned against the default branch, matching the autoUpdate the native install had.
- apm.lock.yaml is committed; .claude/skills/, .claude/agents/ and apm_modules/ are gitignored
  regenerable install output. Committing the deployed skills would add a third mirror of content
  ADR-0017 already governs two copies of.
- .mcp.json is generated by apm from plugins/bin/.mcp.json, so the obsidian MCP server survives
  the switch.
- .claude/settings.json is reduced to {"hooks": {}}. apm replays the install into a scratch tree
  and diffs, so any repo-owned key there is permanent drift that fails apm-audit-ci. Nothing was
  lost: enabledPlugins was empty after the uninstall and the only hooks entry was PreToolUse: [].
- tests/run-bats.sh and tests/run-tests.sh exclude apm_modules/. It holds a full copy of every
  plugin, and a copied .bats file resolves its helpers against the dependency root rather than
  this repo — 334 tests, 167 failures before the exclusion.

Impact:
Skills are now unnamespaced — `git-commits`, not `git:git-commits` — because apm deploys plain
project skills with no plugin to prefix. AGENTS.md, CONTEXT.md and docs/spec/architecture.md are
updated accordingly. Root apm.yml now declares dependencies, which arms apm-audit-ci's
lockfile-exists check for the root manifest. External consumers are unaffected: the marketplace
manifests are untouched and `apm pack --check-clean` stays clean. Project scope only.

ADR: 0018

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01X7GvKuJfy2WrdBmUttV4DT

docs/spec/architecture.md

@@ -19,13 +19,13 @@ project repo (local overrides)
 - **Executables** (`DEPLOY_EXECUTABLES`): `providers/claude-code/statusline-command.sh` → `~/.claude/statusline-command.sh` (with `+x`)
 - **Directories** (`DEPLOY_DIRS`): `core/` → `~/.claude/core/` (destination fully replaced on each deploy)
 
-Skills are **not** deployed by `install.sh`. They are distributed as plugins and installed separately via `claude plugin install <name>@holocron`.
+Skills are **not** deployed by `install.sh`. They are distributed as plugins and installed separately — in this repo by `apm install` against the `dependencies.apm` entries in the root `apm.yml`, which lands them in `.claude/skills/` and `.claude/agents/` (ADR-0018); elsewhere by `claude plugin install <name>@holocron`.
 
 `~/.claude/CLAUDE.md` is a thin adapter, not a content source. It imports `~/.agents/AGENTS.md` (always-on rules) and `governance.md` (always-on governance), then lists the content index. All always-on content lives in `AGENTS.md` files so other providers can import the same source without duplication.
 
 ## Plugin model
 
-Skills, agents, MCP servers, and hooks are distributed as self-contained plugin units under `plugins/`, installed independently via `claude plugin install <name>@holocron`. Each plugin is an **apm package**: `plugins/<name>/apm.yml` plus a hand-authored `plugins/<name>/.apm/{skills,agents,hooks,commands,instructions,extensions}/` tree (ADR-0015). There is no hand-maintained `plugin.json` — every manifest and every host-visible content directory is compiled from that source.
+Skills, agents, MCP servers, and hooks are distributed as self-contained plugin units under `plugins/`, installed independently — via `apm install` here, or `claude plugin install <name>@holocron` for a host consuming the marketplace natively (ADR-0018). Each plugin is an **apm package**: `plugins/<name>/apm.yml` plus a hand-authored `plugins/<name>/.apm/{skills,agents,hooks,commands,instructions,extensions}/` tree (ADR-0015). There is no hand-maintained `plugin.json` — every manifest and every host-visible content directory is compiled from that source.
 
 Two compilers produce the plugin roots you see in the tree: