Major simplification of the FastApply MCP server implementation:

- Remove complex features: dry-run mode, file locking, backup system,
  validation, search functionality, and configuration updates
- Focus on single tool: fast_apply_edit for efficient partial editing
- Implement smart matching with exact and normalized whitespace fallback
- Add XML escaping to prevent prompt injection attacks
- Reduce codebase from ~900 to ~487 lines
- Achieve 80-98% token savings vs full-file editing approach
- Update documentation to emphasize simplicity and efficiency
- Remove fastapply-mcp script alias, keep only fastapply_mcp

BREAKING CHANGE: Removed edit_file and dry_run_edit_file tools.
Use fast_apply_edit instead with target_filepath, original_code,
and code_edit parameters. Removed automatic backups, file locking,
and configuration update capabilities.