docs: add user docs for LightCraft

User docs in docs/user/ (published at getartcraft.com/docs/lightcraft),
the docs-check and docs-publish workflows, and a "User docs" rule in AGENTS.md.
Modelled on the ArtCraft Launcher setup.

Sources per page:
- index.md: README.md, crafting-apps.ts (lightcraft entry), Cargo.toml (0.6.0)
- getting-started/install.md: README Downloads section, `gh release view` v0.6.0 asset list, craft-launcher catalog.rs and install docs
- guides/import-photos.md: crates/ui-egui/src/import.rs, panels/dialogs.rs, menubar.rs, menus.rs
- guides/cull-photos.md: docs/library-shortcuts.md, menubar.rs, panels/compare.rs, README
- guides/edit-a-photo.md: panels/edit.rs, develop/src/controls.rs, menus.rs, README
- guides/export-photos.md: panels/dialogs.rs (Export dialog), menus.rs
- guides/import-lightroom-catalog.md: docs/lightroom-catalog-import.md, menus.rs, issue #832
- troubleshooting/preview-only-raw.md: issue #662, widgets.rs, engine cmd/convert.rs, README
- troubleshooting/raw-photos-look-dull.md: issues #860, #778, #697
- troubleshooting/get-help.md: README (logs), menus.rs Help menu, issue #860
- faq/free-and-private.md: README (local-first, license), ROADMAP link
- faq/supported-files.md: README, menus.rs, export dialog

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.github/workflows/docs-check.yml

@@ -0,0 +1,32 @@
+name: docs-check
+
+on:
+  pull_request:
+    paths: ["docs/user/**"]
+  push:
+    branches: [main]
+    paths: ["docs/user/**"]
+
+permissions:
+  contents: read
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+      - name: Download the shared docs checker
+        id: fetch
+        run: |
+          url=https://raw.githubusercontent.com/storytold/artcraft-services/main/frontend/apps/artcraft-website-next/scripts/docs/core.mjs
+          if curl -fsSL "$url" -o "$RUNNER_TEMP/docs-core.mjs"; then
+            echo "ok=1" >> "$GITHUB_OUTPUT"
+          else
+            echo "::warning::The docs checker is not published yet; skipping."
+          fi
+      - name: Check docs/user
+        if: steps.fetch.outputs.ok == '1'
+        run: node "$RUNNER_TEMP/docs-core.mjs" docs/user

.github/workflows/docs-publish.yml

@@ -0,0 +1,22 @@
+name: docs-publish
+
+on:
+  push:
+    branches: [main]
+    paths: ["docs/user/**"]
+
+permissions: {}
+
+jobs:
+  rebuild:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Rebuild getartcraft.com
+        env:
+          HOOK: ${{ secrets.DOCS_BUILD_HOOK }}
+        run: |
+          if [ -z "$HOOK" ]; then
+            echo "DOCS_BUILD_HOOK is not set; the nightly website build will pick this up."
+            exit 0
+          fi
+          curl -fsS -X POST -d '{}' "$HOOK?trigger_title=docs%20update%20from%20$GITHUB_REPOSITORY"