docs: cut CLAUDE.md to rules-only (179 → 74 lines)

CLAUDE.md now carries only what must be known *before* opening a file:
hard rules, gotchas, and an entry-point table. Everything descriptive
moved to the doc that lives next to the code.

Moved out:
- stack versions, plugin roles, asset pipeline, nav shape, user/ repo
  tracking rules → docs/reference/architecture.md
- Playwright layout, config facts, auth-setup project, test account
  → docs/reference/testing.md (new)
- folder map, full make command list (build/test/demo/worktree targets
  that only existed in CLAUDE.md) → README.md
- dev/prod Twig settings table → already in docs/guides/deploy-cycle.md

Fixed while verifying, all of them descriptions that had drifted:
- demo fixtures were listed as italy-2026-demo + no-photos-demo; the
  actual folders are italy-2025 + italy-2026-demo
- the map engine was cited at js/src/maplibre-utils.js; it is
  js/maplibre-utils.js, a hand-authored file beside the bundles
- the build-output list omitted fonts/ and the generated
  templates/partials/weather-icons.html.twig, and did not flag that
  js/maplibre-utils.js and js/nav.js are sources living in js/
- README called user/ a "standalone git repo" (it is a submodule)
- docs/README.md linked to a non-existent working/production-todo.md
- git-sync-notes.md pointed at "CLAUDE.md §1", a section number that
  no longer exists

Net: ~17.1k → ~8.5k chars of always-loaded context.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/reference/testing.md

@@ -0,0 +1,67 @@
+# Testing
+
+Every suite drives the **live site over HTTP**, so the dev server must be running (`make start`) before any of them.
+
+---
+
+## Commands
+
+| Command | Scope |
+|---|---|
+| `make test` | Everything: `test-config` → `test-post` → `test-ui` |
+| `make test-config` | Form/config sanity via `scripts/test-form-config.sh` |
+| `make test-post` | End-to-end post submission via `scripts/test-post.sh` |
+| `make test-ui` | Playwright suite (`npx playwright test`) |
+| `make test-account` | Creates the `testrunner` admin if absent (a dependency of `test-post` and `test-ui`) |
+
+Focused runs bypass `make`:
+
+```bash
+npx playwright test tests/ui/maps            # one suite
+npx playwright test tests/ui/maps --headed   # watch it
+```
+
+---
+
+## Layout
+
+```
+playwright.config.js         ← config (testDir: ./tests/ui)
+tests/
+├─ global-setup.js           ← runs once before all projects
+├─ global-teardown.js        ← runs once after
+├─ fixtures/
+└─ ui/
+   ├─ helpers.js             ← shared helpers; import from here rather than re-rolling
+   ├─ auth/                  ← includes auth.setup.js (see below)
+   ├─ a11y/  dailies/  gpx/  home/
+   ├─ maps/  nav/  post/  stories/  trip/
+```
+
+---
+
+## Config facts
+
+| Setting | Value | Why it matters |
+|---|---|---|
+| `baseURL` | `process.env.GRAV_BASE_URL \|\| 'http://localhost:8081'` | Set `GRAV_BASE_URL` to test a worktree's isolated server on `8090+` |
+| `retries` | `0` | A failing test is a real failure, not flake — do not paper over it with retries |
+| `timeout` | `30_000` | Per test |
+| `screenshot` | `only-on-failure` | Video off; artifacts stay small |
+| `reporter` | `line` | |
+
+### Auth is a dependency project
+
+Two Playwright projects, in order:
+
+1. **`setup`** — matches `auth.setup.js`, logs in once, writes `tests/.auth/user.json`.
+2. **`chromium`** — `dependencies: ['setup']`, consumes that file as `storageState`.
+
+So every test in `chromium` starts already authenticated. **Never add a per-test login** — it duplicates the setup project and slows the suite.
+
+### The test account
+
+`make test-account` creates a `testrunner` admin (via `bin/plugin login new-user`, admin type `both`) inside the container if `user/accounts/testrunner.yaml` is missing. It is git-ignored.
+
+- Never commit it.
+- Keep the password free of shell/Make/URL-special characters — it is interpolated by the Makefile, `scripts/test-post.sh`, and the Playwright setup, and a special character breaks at least one of them.