feat: add OpenSpec specs and changes for ASW restructure

Specs: repo-structure, 10 framework layer specs, packs, site.
Changes: repo-restructure (10 tasks), css-refactor (12 tasks),
legacy-import (proposal + triage categories).

Supersede docs/css-refactor-plan.md in favor of OpenSpec change.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

openspec/changes/repo-restructure/proposal.md

@@ -0,0 +1,42 @@
+# Proposal: Repository Restructure
+
+## Intent
+
+The ASW repo currently has a flat Hugo-centric layout where framework source, website content, and build tooling are interleaved. This restructure separates the framework (`src/`), its documentation (`docs/`), its engine integrations (`packs/`), its built output (`dist/`), its dependencies (`vendor/`), and its website (`site/`) into clearly bounded directories.
+
+**Goal: anyone landing on this repo immediately understands what ASW is and where things live.**
+
+## Scope
+
+### In Scope
+- Move `assets/css/layers/` → `src/layers/`
+- Move `assets/css/main.css` → `src/main.css`
+- Create `dist/` at root for built output (`asw.css`, `asw.min.css`)
+- Create `vendor/open-props/` with vendored copies + VERSION file
+- Move Hugo files (`content/`, `layouts/`, `hugo.toml`, `archetypes/`) → `site/`
+- Configure Hugo module mount: `docs/` → `site/content/docs/`
+- Restructure `docs/` as engine-agnostic markdown (already mostly there)
+- Create `src/lab/` for experiments
+- Create `examples/` at root for static HTML showcases
+- Update build paths in `postcss.config.js` and `package.json`
+
+### Out of Scope
+- CSS refactor (separate change, works on `src/layers/` after this)
+- Legacy repo import (separate change, lands material after this)
+- Content writing or new docs
+- New pack creation
+
+## Approach
+
+Incremental moves with build verification after each step. The site must remain buildable and deployable throughout.
+
+## Risks
+
+- **Hugo path breakage** — Hugo has opinions about where `assets/` lives. Module mounts should handle this but need testing.
+- **Deploy script breakage** — `deploy.sh` hardcodes paths. Will need updating (or removal if temporary).
+- **Symlink/mount complexity** — `docs/` → `site/content/docs/` via Hugo mount is clean but adds config complexity.
+
+## Files Touched
+
+Primary: `assets/css/`, `content/`, `layouts/`, `hugo.toml`, `postcss.config.js`, `package.json`
+Created: `src/`, `dist/`, `vendor/`, `site/`, `examples/`, `src/lab/`