cli.ts resolved the Chromium profile dir with a hardcoded
$HOME/.gstack/chromium-profile, while browser-manager launches the profile
returned by config.resolveChromiumProfile(), which honours CHROMIUM_PROFILE
and GSTACK_HOME.
killOrphanChromium() and cleanChromiumProfileLocks() are called with no
argument, so whenever CHROMIUM_PROFILE was set they cleaned locks for, and
killed Chromium on, the DEFAULT profile rather than the one being launched.
Starting a browser with a custom profile therefore evicted an unrelated
browser running on the default profile.
Delegating to resolveChromiumProfile() also picks up GSTACK_HOME and
os.homedir(), so the cleanup path now matches the launch path on Windows
where HOME is frequently unset.
