Replace --custom-field, --kb-accept, and --kb-custom CLI flags with a
YAML config file at $XDG_CONFIG_HOME/bw-menu/config.yaml. The config
maps rofi key names to vault fields (e.g. Return: password), making
keybinding configuration simpler and more intuitive.
Replace bw-serve/Ansible-based implementation with a clean rewrite:
- rbw CLI wrapper for listing entries and fetching credentials
- Rofi script-mode and fzf selectors with history-first sorting
- JSON-backed frecency history at ~/.cache/bw-menu/
- Clipboard support via wl-copy/xclip auto-detection
- uv + hatchling packaging with bw-menu entry point
