Addresses the footgun raised in issue #1 follow-up: plain `--launch` silently
uses a temporary EMPTY profile (no cookies/login), and the connect-failure
error even recommended it — trapping agents into thinking they reused the
logged-in browser when they didn't.
- `--profile auto`: resolves to the Chrome profile last used (from Local State
`profile.last_used`), falling back to "Default", then the first profile. So
`--launch --profile auto open <url>` reuses real login state without naming
the profile. (--profile <name>/Default already worked.)
- connect-failure error now recommends `--launch --profile auto` and states
plainly that bare `--launch` is a temporary EMPTY profile — no cookies/login.
- bare `--launch` (no --profile, not CI) now prints a warning to that effect.
- README: fix Setup (relaunch with --remote-debugging-port, not chrome://inspect)
and split Standalone mode into throwaway vs. keep-your-login (`--profile auto`).
Tests: resolve_chrome_profile("auto") prefers last_used, falls back to Default.