A click on a target=_blank link / window.open opened a new tab, but the active
tab stayed put, so the post-click snapshot showed the OLD page — looking exactly
like the click failed. On the relay the new tab is discovered only via getTargets
(the relay doesn't push target events to the daemon), so it went unsurfaced.
handle_click now snapshots tracked targets before the click and, after, runs a
lightweight BrowserManager::adopt_newly_opened (one getTargets, attaches only the
new target — far cheaper than a full resync) to detect a freshly-opened tab. It's
reported as openedTab {tabId,url,title} in the response (and a '→ opened new tab
[tN] <url>' hint in text mode). Default keeps focus on the current tab (so
multi-tab flows aren't hijacked, per #7/#8.1); 'click <sel> --follow' switches to
the new tab. Verified live: clicking a _blank link prints
'→ opened new tab [t13] https://example.org/'.
Completes the #24 friction items (B/C/D shipped in 770708b).