Ship native subagent definitions for GitHub Copilot and Cursor

The github and cursor providers previously received only the generated
degraded/ inline fallbacks. Both harnesses support real custom subagents,
so the build now emits them from the same skill/agents/ source:

- GitHub Copilot: .github/agents/impeccable-<role>.agent.md with portable
  frontmatter only (name + description; omitting tools grants all tools,
  and Copilot has no documented model/effort/max-turns equivalents).
- Cursor: .cursor/agents/impeccable-<role>.md with name, description,
  model: inherit, is_background: false, and readonly derived from the
  agent's tool list (true only for the finish reviewer, which declares
  neither Write nor Edit). effort/max-turns are skipped because Cursor's
  effort option requires an explicit model id.

Agent bodies now also resolve {{scripts_path}} and strip rule markers in
the shared agentFormat pipeline, which fixes the previously unresolved
placeholder in the emitted Claude asset-producer agent.

The CLI installer places agents per scope: project installs write
<repo>/.github/agents/ and <repo>/.cursor/agents/; user-level installs
write ~/.copilot/agents/ (Copilot's user dir, not ~/.github/) and
~/.cursor/agents/, overwriting stale impeccable-* copies. Because
Copilot lets user-level agents shadow same-named project ones, a project
install warns when shadowing copies exist; Cursor gives project agents
precedence, so no warning there.

new-work.md and visualize.md extend their harness-naming clauses with
the Cursor and Copilot invocations. The degraded/ fallbacks keep
shipping for surfaces where the model still fails to delegate.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

skill/reference/visualize.md

@@ -36,6 +36,6 @@ Treat the comp as a north star, not something to trace, and know what that allow
 
 Generation context is part of the asset: the thread that wrote a prompt knows what the image contains, why, and how it is meant to sit in the layout, and a build composed by a thread without that knowledge places assets it does not understand. So prefer generating build-critical imagery in the build thread when the budget allows, and when a subagent produces assets instead, every asset must carry its prompt, and the builder reads those prompts before composing a single one of them. The carrier is uniform across harnesses: after generating any image with any tool, native or `generate-image.mjs` (which does it automatically), run `node {{scripts_path}}/embed-prompt.mjs <image> --prompt "<the prompt used>"` so the intent lives inside the file itself and survives copies between machines and harnesses; `--read` recovers it from any impeccable-generated image.
 
-When clean raster ingredients are required and the harness runs subagents, use the shipped asset producer, `impeccable-asset-producer` (`impeccable_asset_producer` in codex): give it the approved comp, output paths, required dimensions and formats, transparency needs, crop notes, and what must remain semantic code. Otherwise produce the minimum required assets in the current thread by the book: load [degraded/asset-producer.md](degraded/asset-producer.md) and follow it inline, with whatever generation exists, the native tool or generate-image.mjs.
+When clean raster ingredients are required and the harness runs subagents, use the shipped asset producer, `impeccable-asset-producer` (`impeccable_asset_producer` in codex; `/impeccable-asset-producer` in Cursor; on GitHub Copilot say "Use the impeccable-asset-producer agent"): give it the approved comp, output paths, required dimensions and formats, transparency needs, crop notes, and what must remain semantic code. Otherwise produce the minimum required assets in the current thread by the book: load [degraded/asset-producer.md](degraded/asset-producer.md) and follow it inline, with whatever generation exists, the native tool or generate-image.mjs.
 
 Return to [new-work.md](new-work.md) for the direction contract, implementation, and the finishing pass.