refactor: rename fragments directory to ingredients and update all references

- Directory rename: fragments/ → ingredients/ (54 .ks files)
- Updated all Python scripts:
  * tests/integration/conftest.py - fixture renames
  * tests/integration/test_integration.py - constant and path updates
  * tests/test_recipe_generator.py - updated test assertions
  * recipe-generator/validators.py - updated comments and error messages
  * recipe-generator/recipe_generator.py - updated comment
- Updated all YAML files:
  * recipe-generator/recipe_templates.yaml - 66 path references
  * .gitea/workflows/validate-fragments.yaml → validate-ingredients.yaml
  * .gitea/workflows/test-generation.yaml - path patterns
- Updated scripts:
  * bin/ksflatten-relative - updated path detection
- Updated test file:
  * tests/integration/test_fragments.py → test_ingredients.py
- Updated documentation:
  * DEVELOPMENT.md - simplified references
  * DEVELOPMENT_QUICK.md - updated examples
  * tests/container/README.md - test references
- Regenerated all recipes (16 files) with ingredient paths
- Updated test fixtures (7 files)
- All integration tests pass (5/5)
- All unit tests pass (29/31 - 2 pre-existing failures unrelated)

ingredients/desktop/labwc/config.ks

@@ -0,0 +1,19 @@
+# Untested
+
+xconfig --startxonboot # Start the display session on boot. Although it says --startx, which seems to imply xorg, it is actually generic and thus works also with Wayland.
+
+%packages --exclude-weakdeps # Beginning of the packages section. Excludes weak package dependencies.
+
+@base-graphical
+## provides the following as mandatory packages:
+# mesa-dri-drivers
+# mesa-vulkan-drivers
+# plymouth-system-theme
+
+labwc # A Wayland window-stacking compositor
+
+## Extra hand-picked packages
+firefox # Mozilla Firefox Web browser
+mozilla-ublock-origin.noarch # An efficient blocker for Firefox
+
+%end # End of the packagages section