Launcher WKAPPBOT_CHROME_TARGET env + pipe protocol

Launcher publishes validated caller-offset Chrome placement target via WKAPPBOT_CHROME_TARGET env var AND forwards through Eye command pipe with __target prefix. Core reads same coords so SetWindowPos, post-launch stability loop, and per-command reposition all use Launcher-computed target. Without this Core falls back to ExpectedBounds (rightmost monitor anchor) and fights Launcher SetWindowPos producing wrong-monitor regression.

Steps