fix(domains): restore fail-closed focus check in browser_type

Adopting isFocusProbe inverted the safety default: the guard was ANDed into
the condition gating the check, so a probe result the guard rejected skipped
the check and fell through to Input.insertText — text typed into nothing,
silently, which is the exact failure the block exists to prevent. The guard
now feeds a value that defaults to { ok: false }, so a rejected shape
produces the error instead of bypassing it.

The other four guard adoptions (isFillResult, isFocusResult, isSelectResult,
isPageResult) were already fail-closed: each feeds a value whose rejection
lands on a pre-existing error branch.

Also assert x/y in the box centre test — the fields snapshot's off-viewport
filter reads — and wrap the zero-size message to the surrounding width.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

0 files changed, 0 insertions, 0 deletions