why: Need consistent YAML writing functionality for new CLI commands
what:
- Add save_config_yaml function to centralize config file writing
- Use ConfigReader._dump for consistent formatting
refs: Foundation for add/add-from-fs commands

why: Users need a way to manually add individual repositories to config
what:
- Add command to add single repository by name and URL
- Support custom base directory with --dir option
- Support path inference with --path option
- Check for duplicates and warn appropriately
- Use verbose format {"repo": "url"} for new entries

...ition
why: Users with many existing repos need efficient bulk import
what:
- Scan directories for git repositories
- Extract origin URLs from git config
- Support recursive scanning with -r/--recursive
- Custom base directory key with --base-dir-key
- Auto-confirm with -y/--yes
- Show summary for large numbers of existing repos

why: Sync function needs to handle cases where config is not specified
what:
- Change sync function signature to accept optional config
- Update CLI handler to properly pass config parameter

why: CLI commands need user-friendly output without log prefixes
what:
- Add SimpleLogFormatter class for message-only output
- Configure CLI modules (add, add_from_fs, sync) to use simple formatter
- Maintain debug formatter for core vcspull logger
- Set propagate=False to prevent duplicate logging

why: Ensure add command functionality is properly tested
what:
- Test simple repository addition
- Test custom base directory handling
- Test duplicate detection
- Test adding to existing config

...canner
why: Ensure add-from-fs functionality works correctly
what:
- Test git origin URL extraction
- Test single and multiple repo discovery
- Test recursive and non-recursive scanning
- Test user confirmation flow
- Test existing repo handling
- Test output formatting for many repos

why: Ensure logging infrastructure works as expected
what:
- Test SimpleLogFormatter output
- Test RepoLogFormatter functionality
- Test DebugLogFormatter with various log levels
- Test logger configuration and propagation

why: Some CLI output goes to stderr and was being missed
what:
- Capture both stdout and stderr in test_sync_cli_filter_non_existent
- Ensures complete output validation in test

why: Tests didn't follow established vcspull testing patterns
what:
- Convert to parameterized tests using AddRepoFixture(NamedTuple)
- Test through CLI entry point instead of direct function calls
- Add clear_logging_handlers fixture to prevent stream closure issues
- Remove caplog.set_level() calls that were causing handler conflicts
- Maintain full test coverage with improved organization
refs: #tests

...entions
why: Tests didn't follow established vcspull testing patterns and had logging issues
what:
- Convert to parameterized tests using AddFromFsFixture(NamedTuple)
- Test through CLI entry point for integration testing
- Add helper functions setup_git_repo() and clone_repo() for test setup
- Add clear_logging_handlers fixture to prevent stream closure issues
- Remove caplog.set_level() calls that were causing handler conflicts
- Improve test organization and maintain full coverage
refs: #tests

...ception handler
why: Match established error handling patterns in the codebase
what:
- Change raise to return in save_config_yaml exception handler
- Maintains consistency with other modules' error handling approach

...se in exception handler
why: Match established error handling patterns in the codebase
what:
- Change raise to return in save_config_yaml exception handler
- Maintains consistency with other modules' error handling approach

why: Address ruff linting warnings to improve code quality and consistency
what:
- Move traceback imports to module level instead of conditional imports
- Convert f-string logging to % formatting for better performance
- Fix line length issues to meet 88 character limit
- Maintain all functionality while improving code style
All tests passing after changes.

why: Follow imperative mood convention for docstrings (D401)
what:
- Change "Helper to set up" to "Set up" in setup_git_repo docstring
- Change "Helper to clone" to "Clone" in clone_repo docstring
refs: D401 ruff rule

why: Users need a way to standardize and clean up their vcspull configurations
what:
- Add format_config_file function to format vcspull configs
- Implement normalize_repo_config to convert compact to verbose format
- Convert url keys to repo keys for consistency
- Sort directories and repositories alphabetically
- Add --write flag requirement for actual file modification
- Show detailed summary of changes when run without --write

why: Wire up the fmt command to the main CLI interface
what:
- Import fmt module and format_config_file function
- Add fmt_parser to subparsers with help text
- Add fmt handling in cli() function with config and write arguments
- Update create_parser return tuple to include fmt_parser

why: Ensure fmt command works correctly with various config formats
what:
- Add TestNormalizeRepoConfig class for testing repo normalization
- Add TestFormatConfig class for testing config formatting logic
- Add TestFormatConfigFile class for testing file operations
- Test compact to verbose format conversion
- Test url to repo key conversion
- Test directory and repository sorting
- Test --write flag behavior and dry-run mode
- Add clear_logging_handlers fixture to prevent test interference