Replace the old "skips download when a system browser exists" assertions with
tests for the new behavior:
- no PATH scan for browser command names, and the "use the system browser" path
is gone;
- find_system_browser consults only an explicit AGENT_BROWSER_EXECUTABLE_PATH
override (which still skips the bundled download);
- strip_snap_browser_override runs on both install paths and a /snap/* path is
rejected, so already-affected installs auto-recover on update.
The Debian/Ubuntu branch of install_node_deps() ran 'npx playwright install
--with-deps chromium' unconditionally. Playwright invokes sudo interactively
to apt-install Chromium's system libraries, which blocks the installer for
non-sudo users (systemd service accounts, unprivileged operator users) on
an unsatisfiable password prompt.
Changes:
- install.sh: gate --with-deps behind a sudo capability check on the apt
branch (matches the existing Arch/pacman branch pattern). Non-sudo users
fall back to 'npx playwright install chromium' alone and the installer
prints the exact 'sudo npx playwright install-deps chromium' command an
administrator can run separately.
- install.sh: add --skip-browser (alias --no-playwright) to skip the
Playwright step entirely for headless installs that don't need browser
automation. Mirrors the existing --no-venv / --skip-setup shape.
- installation.md: add a 'Non-Sudo / System Service User Installs' section
covering the admin/service-user split, the --skip-browser flag, and the
~/.local/bin PATH gotcha (the root cause of the 'No module named dotenv'
error users hit when running the repo source 'hermes' script with system
Python instead of the venv launcher).
- test_install_sh_browser_install.py: regression coverage for the
--skip-browser flag and the sudo-gate on the apt branch.
Reported by @ssilver in Discord.
