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)

tests/integration/conftest.py

@@ -27,9 +27,9 @@ def project_root():
 
 
 @pytest.fixture
-def fragments_dir(project_root):
-    """Return fragments directory."""
-    return project_root / 'fragments'
+def ingredients_dir(project_root):
+    """Return ingredients directory."""
+    return project_root / 'ingredients'
 
 
 @pytest.fixture
@@ -39,9 +39,9 @@ def recipes_dir(project_root):
 
 
 @pytest.fixture
-def fragments(fragments_dir):
-    """List all .ks fragment files."""
-    return list(fragments_dir.glob('**/*.ks'))
+def ingredients(ingredients_dir):
+    """List all .ks ingredient files."""
+    return list(ingredients_dir.glob('**/*.ks'))
 
 
 @pytest.fixture