Improve slugify function, add tests, and enhance Makefile

Applied improvements from feature-code-quality branch:
- Refactored slugify() for better readability with inline comments
- Renamed log() parameter *args to *log_args (avoid shadowing built-in)
- Added comprehensive unit tests for slugify function
- Enhanced Makefile with typecheck and test targets
- Updated build target to run type checks and tests before Docker build

All tests pass and type checking succeeds.

Makefile

@@ -1,15 +1,28 @@
-# Makefile 
+# Makefile
 
-# build target should be built even if no files depend on it
-.PHONY: build
+# declare phony targets
+.PHONY: build test typecheck
 
 # run locally
-site:	
+site:
 	uv run python makesite.py --params params-local.json
 	cd _site && python -m SimpleHTTPServer 2> /dev/null || python3 -m http.server
 
+# run type checks
+typecheck:
+	uv run mypy makesite.py monitor.py
+
+# run unit tests
+test:
+	uv run python -m unittest discover test -v
+
 # docker build image
-build:	
+build:
+	@echo "Running type checks..."
+	uv run mypy makesite.py monitor.py
+	@echo "Running tests..."
+	uv run python -m unittest discover test -v
+	@echo "Building Docker image..."
 	docker build -t source.madyanne.fr/yax/blog .	
 		
 # docker publish image