feat(plugin): ship the repo's skills as ccam plugin skills

The repo root already IS the `ccam` plugin root (`"source": "./"`), so the
conventional `skills/` dir at the root is the plugin's skills dir — while
`.claude/skills/` only loaded for a session whose cwd was inside this
checkout. That is useless for a lane working in another repo, which is why
`ccam skills install` existed at all.

Move all seven skills to `skills/`: they now reach every plugin user as
`/ccam:<name>` (bare `/<name>` as an alias). `ccam skills install` stays as
the fallback for a plain checkout without the plugin, sourcing from the new
path.

Agents deliberately do NOT move. A plugin agent is addressed as
`ccam:qc-local`, which would break the `subagent_type: qc-local` references
in ship-feature-lane; `ccam lanes agents install` keeps writing them into the
lane's own `.claude/agents/`, the highest-priority agent source. MCP was
already plugin-shipped via `plugins/ccam/.mcp.json`.

Mechanical fallout: ~115 source files carry a doc-comment pointer to
`.claude/skills/file-headers/`, repointed to `skills/file-headers/`. The
generic Claude Code config-surface examples in openapi/cc-config (`.claude/
skills/code-reviewer`) describe any user's layout and are left alone.

Also fixes the two file-headers scripts, whose `ROOT=` climbed four levels
from `.claude/skills/file-headers/scripts/` and would have escaped the repo
from the new depth — it scanned sibling projects until corrected to three.

npm run test:server (1160 pass), test:client (422 pass), mcp:typecheck,
mcp:build + mcp:check-build all green.

skills/ship-feature/SKILL.md

@@ -0,0 +1,134 @@
+---
+name: ship-feature
+description: Implement a feature safely end-to-end in this repository. Use when adding or changing functionality across backend, frontend, or MCP with required verification and documentation updates. Drives the Superpowers workflow skills and declares each phase with `ccam stage` so the dashboard's pipeline map follows along.
+---
+
+# Ship Feature
+
+Use this workflow for medium or large implementation tasks. It does not restate
+how to plan, test, or review — the Superpowers skills own that. What lives here
+is the phase order, this repository's own rules, and the stage declaration at
+each boundary.
+
+For a feature inside a CCAM **lane**, use `ship-feature-lane` instead: it adds
+the branch/e2e/QC/senior-gate/PR half this skill deliberately leaves out.
+
+## Declaring the stage
+
+Each phase below starts with `ccam stage <node>`, which is what puts the phase
+on the lane's pipeline map. The nodes are the `default` template's:
+`intake → plan → implement → tests → review → gate → ship → done`.
+
+Set the template yourself, don't rely on how the lane was created: before your
+first `ccam stage` call, run `ccam lanes pipeline default` (no id needed —
+resolves from `cwd`; a no-op if the lane is already on it). This is what makes
+the choice invisible to the human — whichever of `ship-feature` or
+`ship-feature-lane` actually runs is what decides the template, not a picker
+they have to get right in advance.
+
+`ccam stage` needs a lane owning the current directory. If it reports no lane,
+this repo was never adopted (`ccam lanes add --cwd $(pwd)` fixes it) — carry on
+with the workflow and skip the stage calls; they are reporting, not control
+flow. Never skip a phase because its stage call failed.
+
+Declaring beats detection. The dashboard also *infers* these stages from the
+Superpowers skill invocations below, but an inference never renders `done` and
+never overrides a declaration — and detection cannot move a lane BACKWARD past
+a declared stage, so a rework loop is invisible unless you re-declare the phase
+you dropped back to.
+
+## Phases
+
+### intake — understand before touching anything
+- `ccam stage intake --status running`
+- Restate the requirement and its success criteria.
+- Explore the impacted modules: `Explore` agent for breadth, then read the key
+  files yourself. Identify which layers are hit (server / client / mcp / docs /
+  scripts) — `repo-onboarding` if the area is unfamiliar.
+- Requirement fuzzy or open to more than one reading? **superpowers:brainstorming**.
+
+### plan — a written plan, challenged before it is code
+- `ccam stage plan`
+- **superpowers:writing-plans**: approach, files to change, the test strategy
+  (which behavior each test pins), and how each success criterion is met.
+- If the task is a bug rather than a feature: **superpowers:systematic-debugging**
+  first. Root cause, not symptom — and grep every caller of the function you
+  are about to change, not just the path the report names.
+- Have the plan **challenged by a fresh-context agent** (`Plan` or
+  `general-purpose`, never `fork`): missed requirements, wrong assumptions, a
+  simpler approach, unhandled edge cases. Give it the requirement and the plan,
+  not your reasons for believing the plan. Apply what survives
+  **superpowers:receiving-code-review** scrutiny.
+
+### implement — smallest coherent diff
+- `ccam stage implementing`
+- **superpowers:test-driven-development**: failing test → minimal code → green.
+- Smallest diff that satisfies the requirement. Every changed line traces to it.
+- **file-headers** applies to every source file you create or edit.
+
+### tests — this repo's verification, not a claim
+- `ccam stage tests --status running`
+- **Dispatch, don't self-grade.** Both halves below run in a **fresh-context
+  agent** (Agent tool, `subagent_type: general-purpose` — FOREGROUND, and
+  **never `fork`**: a fork inherits your context, which is the bias you are
+  trying to escape). Hand it only what it can verify itself — repo path, the
+  spec/requirement, `git diff` range, the commands — never your own conclusions.
+  - **Independent unit tests.** It reads the requirement and the diff cold and
+    writes the tests the implementation is *missing* — happy, negative and
+    boundary, in the repo's existing style. It may not touch non-test files nor
+    weaken existing tests. Final line: `UNIT-TESTS: PASS — <n> added` or
+    `UNIT-TESTS: FAIL — <test> :: <defect>`.
+  - **Suite run.** Backend changed → `npm run test:server`. Frontend →
+    `npm run test:client`. MCP → `npm run mcp:typecheck` + `npm run mcp:build`.
+    A UI snapshot diff is reported for review, **never blindly regenerated**
+    (`cd client && npx vitest run -u` is yours to run, only after you read the
+    diff).
+- `FAIL` → fix the **source** (root cause), not the agent's test — then re-run
+  this phase. Rewriting a failing independent test to pass is the one move that
+  makes this whole phase worthless.
+- Record the outcome: `ccam stage tests --evidence "<what passed>"`, or
+  `--result fail` with what failed. A step you could not run is reported as not
+  run, never as passed.
+
+### review — a real review pass, not a re-read
+- `ccam stage review --status running`
+- Hand the review to a **fresh-context agent** (`subagent_type: Code Reviewer`,
+  FOREGROUND, never `fork`) — a reviewer that watched you write the code is not
+  a reviewer. It runs the **code-review** skill on the working diff
+  (see also **superpowers:requesting-code-review** for what to hand over).
+  Final line: `REVIEW: CLEAN` or `REVIEW: FINDINGS — <n>`.
+- Apply what is worth applying with **superpowers:receiving-code-review**
+  judgment: verify each point, neither blind agreement nor blind rejection.
+- Changed code in response? Re-run the `tests` phase.
+
+### gate — evidence before the completion claim
+- **superpowers:verification-before-completion**. Commands actually run, output
+  actually read. This is the phase that stops "should work" from shipping.
+- For a change of any real size, the gate is a **fresh-context agent** too
+  (`general-purpose`, FOREGROUND, never `fork`): hand it the requirement, the
+  diff range and the verification commands — not your evidence — and let it
+  re-run and re-check them. Final line: `GATE: GO` or `GATE: NO-GO — <what is
+  missing>`. A one-line fix does not need it; anything you would defend in a
+  review does.
+- `ccam stage gate --evidence "<what was verified>"`
+
+### ship — docs, then the user's call
+- `ccam stage ship`
+- **update-project-docs** — mandatory for any change to behavior, config,
+  interfaces, events, schema, CLI commands, or features. Not optional, not
+  deferred, not "if asked".
+- Commit / push / PR **only when the user asks in this turn**. Finishing an
+  implementation is not authorization to commit.
+- `ccam stage done --status passed --evidence "<what shipped>"`
+
+## This repository's own rules
+
+Not restated here. `CLAUDE.md` is loaded in every session and already binds
+them — backward-compatible API/WebSocket contracts, fail-safe hooks,
+migration-safe schema changes, the destructive-lane and git-argv guards, and
+the lane boundaries (the console never writes a stage; the runtime never writes
+`stage`/`status`/`notes`). A second copy here would only drift out of sync with
+the first. Read `CLAUDE.md` and `.claude/rules/` for the area you are touching.
+
+## References
+- Checklist template: `references/feature-checklist.md`

skills/ship-feature/references/feature-checklist.md

@@ -0,0 +1,22 @@
+# Feature Checklist
+
+- Scope
+  - Problem and success criteria are explicit.
+  - Impacted layers identified (server/client/mcp/docs/scripts).
+
+- Implementation
+  - Input validation and error handling are explicit.
+  - Existing behavior preserved where not in scope.
+  - Safety controls preserved.
+
+- Verification
+  - Backend: `npm run test:server` when backend changed.
+  - Frontend: `npm run test:client` when UI changed.
+  - MCP: `npm run mcp:typecheck` + `npm run mcp:build` when MCP changed.
+
+- Documentation
+  - `README.md`, `ARCHITECTURE.md`, `SETUP.md`, `INSTALL.md`, `mcp/README.md` updated as needed.
+  - Commands in docs match `package.json`.
+
+- Delivery
+  - Known risks and unrun checks are clearly stated.