refactor(drivers): organize backup modules into drivers subfolder

- Move all backup_*.py files to libtisbackup/drivers/ subdirectory
- Move XenAPI.py and copy_vm_xcp.py to drivers/ (driver-specific)
- Create drivers/__init__.py with automatic driver imports
- Update tisbackup.py imports to use new structure
- Add pyvmomi>=8.0.0 as mandatory dependency
- Sync requirements.txt with pyproject.toml dependencies
- Add pylint>=3.0.0 and pytest-cov>=6.0.0 to dev dependencies
- Configure pylint and coverage tools in pyproject.toml
- Add conventional commits guidelines to CLAUDE.md
- Enhance .gitignore with comprehensive patterns for Python, IDEs, testing, and secrets
- Update CLAUDE.md documentation with new structure and tooling

Breaking Changes:
- Drivers must now be imported from libtisbackup.drivers instead of libtisbackup
- All backup driver files relocated to drivers/ subdirectory

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

.gitignore

@@ -1,21 +1,137 @@
-*.bak
-*.swp
-*~
+# ===============================================
+# TISBackup .gitignore
+# ===============================================
+
+# Python compiled files
+# ===============================================
 *.pyc
+*.pyo
+*.pyd
 __pycache__/
+*.so
+*.egg
+*.egg-info/
+dist/
+build/
+*.whl
+
+# Python virtual environments
+# ===============================================
 .venv/
+venv/
+env/
+ENV/
+.Python
+
+# IDE and editor files
+# ===============================================
+.idea/
+.vscode/
+*.swp
+*.swo
+*~
+.DS_Store
+Thumbs.db
+*.sublime-project
+*.sublime-workspace
+
+# Testing and coverage
+# ===============================================
+.pytest_cache/
+.coverage
+.coverage.*
+htmlcov/
+.tox/
+.nox/
+coverage.xml
+*.cover
+.hypothesis/
+
+# Linting and type checking
+# ===============================================
 .ruff_cache/
 .mypy_cache/
+.dmypy.json
+dmypy.json
+.pylint.d/
+
+# Backup and temporary files
+# ===============================================
+*.bak
+*.backup
+*.tmp
+*.temp
+*.old
+*.orig
+*.log
+*.log.*
+
+# TISBackup runtime files
+# ===============================================
+# Task queue database
 /tasks.sqlite
 /tasks.sqlite-wal
-/srvinstallation
 /tasks.sqlite-shm
-.idea
-/deb/builddir
+
+# Local configuration (samples are tracked, local overrides are not)
+/tisbackup-config.ini
+/tisbackup_gui.ini
+
+# Backup data and logs (should never be in git)
+/backups/
+/log/
+*.sqlite-journal
+
+# Build artifacts
+# ===============================================
+/deb/builddir/
 /deb/*.deb
-/lib
 /rpm/*.rpm
-/rpm/RPMS
-/rpm/BUILD
+/rpm/RPMS/
+/rpm/BUILD/
 /rpm/__VERSION__
-docs-sphinx-rst/build/
+/srvinstallation/
+
+# Documentation builds
+# ===============================================
+docs-sphinx-rst/build/
+docs/_build/
+site/
+
+# Package manager files
+# ===============================================
+pip-log.txt
+pip-delete-this-directory.txt
+
+# OS generated files
+# ===============================================
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+ehthumbs.db
+Thumbs.db
+Desktop.ini
+
+# Secret and sensitive files
+# ===============================================
+*.pem
+*.key
+*.cert
+*.p12
+*.pfx
+.env
+.env.*
+!.env.example
+secrets/
+private/
+
+# Claude Code files
+# ===============================================
+.claude/
+
+# Project specific
+# ===============================================
+# Legacy library (should use libtisbackup instead)
+/lib/