* pi-agent stack
* fix: hardcode pi binary path, set XDG env for npm
npm prefix discovery fails in systemd and activation contexts
because NPM_CONFIG_USERCONFIG and XDG_DATA_HOME are not set.
Hardcode the known path ~/.local/share/npm/bin/pi instead.
- Add chromium to netty system packages
- Add home/agent-browser.nix: configures agent-browser to use nix
chromium headless, installs via npm on first activation (Linux only)
- Add scripts/sync-bw-browser-auth.sh: imports all BW login items
into agent-browser encrypted auth vault via --password-stdin
- Add just sync-browser-auth target
