Create both home-manager and nix-darwin modules for aerospace window
manager configuration, removing 110+ lines of duplicated config from
machine-specific files.
Changes:
- Add home/modules/aerospace module with configurable leader key
- Add modules/aerospace.nix for system-level macOS settings
- Include autoraise configuration in home module
- Update home-darwin-work.nix to use new modules
- Update johno-macbookpro configuration to use system module
- Remove inline aerospace/autoraise config and launchd agents
