fix: reconnect real-click audit after page target replacement

[mergemaven11]

Blocks completion of #206 after its refreshed Frontend CI exposed the existing full-page navigation race.

What changed

• Reconnect the Chrome DevTools Protocol client when a legitimate full-page navigation replaces/detaches the active page target.
• Re-enable Page/Runtime domains after reconnecting.
• Reinstall idempotent click-audit runtime instrumentation (browser error capture, clipboard/media mocks, speech-recognition mock) on the replacement target and for future documents.
• Recover only known navigation/detach errors; real JavaScript/runtime failures remain fatal.
• Recover if the mouse-release command itself races target replacement.

Why

BragStack currently uses full-page internal navigation in several authenticated surfaces. The real-browser click audit was retrying Runtime.evaluate on the old detached target and could never recover, producing Not attached to an active page even when the link itself was valid.

Supersedes the insufficient closed attempt #195, which retried the same dead CDP session without reconnecting.

Merge gate

Merge only if Backend CI, Frontend CI, and Security CI are green on this exact head, the PR remains current/mergeable, and there are no unresolved review threads.