Add undo/redo stack for tag operations (assign, remove, rename, merge) with Ctrl+Z/Ctrl+Y

.gitignore

@@ -1,19 +1,48 @@
-.venv/
+# Python
 __pycache__/
-*.pyc
+*.py[cod]
+*.pyo
+*.pyd
+
+# Virtual environments
+.venv/
+venv/
+env/
+
+# Distribution / packaging
+build/
+dist/
+*.egg-info/
+*.spec.bak
+
+# Testing
 .pytest_cache/
 .mypy_cache/
-build/
-.claude/
-.env
+.coverage
+htmlcov/
 
-# Config a temp soubory
+# Environment
+.env
+*.env.local
+
+# IDE
+.vscode/settings.json
+.idea/
+
+# Claude
+.claude/
+.claudeignore
+
+# App temp / tag soubory
 *.!tag
 *.!ftag
 *.!gtag
 
-# Documentation not to commit
+# Data samples (binary/media, not source)
+data/samples/
+
+# Documentation not for commit
 DESIGN_DOCUMENT.md
 AGENTS.md
-.claudeignore
-TEMPLATE.md
+TEMPLATE.md
+CLAUDE.md