Refactor CodeProcessor to use safe state-machine and tokenize-based stripping, add Jinja {# #} support, and introduce unit tests with Makefile targets

- Added LanguageSpec dataclass and mapping for extensions
- Implemented state-machine for C/CPP/JS comment stripping (handles strings correctly)
- Improved Python comment/docstring removal using tokenize
- Added regex-based stripping for hash (#) and Jinja {# #} comments
- Added Makefile with test and install targets
- Added unit test suite under tests/unit covering Python, C-style, hash, and Jinja cases
- Added compress/decompress roundtrip test
- Added directory handler tests

See: https://chatgpt.com/share/68e0250f-40d4-800f-911d-2b4700246574

Makefile

@@ -0,0 +1,17 @@
+# Makefile for ARC
+.PHONY: test install help
+
+help:
+	@echo "Targets:"
+	@echo "  make test     - Run unit tests"
+	@echo "  make install  - Show how to install via Kevin's Package Manager"
+
+test:
+	@python -m unittest discover -s tests -p "test_*.py" -t .
+
+install:
+	@echo "ARC is distributed via Kevin's Package Manager."
+	@echo "Install it with:"
+	@echo "    package-manager install arc"
+	@echo ""
+	@echo "(This 'make install' does not perform any other actions.)"