With the split open, every app-level terminal action resolved against
Pane A: Ctrl+L typed into Pane B cleared Pane A's display while xterm
sent the ^L into Pane B's PTY, and Ctrl+Shift+R restored Pane A's size.
_focusedPane() now answers with the terminal focused LAST (a mic or
header click moves DOM focus but not the user's pane): Pane B claims it
from its own textarea's focus, the primary terminal's focus gives it
back, and a destroyed pane never holds it. Ctrl+L, Ctrl+Shift+R, voice
dictation and image paste act on the focused pane. Ctrl+W deliberately
still closes the active session: it kills with no confirm, so moving it
is an owner decision (docs/tile-grid-plan.md, decision 5).
Also destroys every tile after each terminal-tile-input test: a real
reconnect timer from one test opened a socket in a later one and flaked
under full-suite load.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>