Initial commit: Brevet card LaTeX sources

Add LaTeX templates for 200km brevet cards with front and back
sides. Includes Docker-based build system and documentation.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,24 @@
+# LaTeX build artifacts
+*.aux
+*.log
+*.out
+*.toc
+*.synctex.gz
+*.fls
+*.fdb_latexmk
+
+# Rendered PDFs
+*.pdf
+
+# macOS
+.DS_Store
+
+# Editor files
+*.swp
+*.swo
+*~
+.vscode/
+.idea/
+
+# Claude Code
+.claude/