refactor: Remove filename deduplication to generate all 24 variants

- Removed deduplication logic from cli.py
- All 24 variants now processed (some overwrite with same filename)
- manifests: Added comments explaining cartesian product and filename behavior
- tests: Updated assertions for correct filename generation order
- Added 3 new tests for guest_agents and hardware_support modifiers

tests/integration/test_integration.py

@@ -37,7 +37,7 @@ def test_validate_all_generated_recipes():
     """Test validating all generated recipes."""
     # Count generated recipes
     recipe_count = len(list(RECIPE_DIR.glob('*.cfg')))
-    assert recipe_count > 0, "No recipes generated"
+    assert recipe_count > 0, f"Expected recipes, got {recipe_count}"
     
     # Validate each recipe
     for recipe_file in RECIPE_DIR.glob('*.cfg'):