When switching sessions in loadSession(), the window._compressionUi state
was not cleared, causing phantom 'Compressing context' barriers to appear
on fresh sessions that never triggered compression.
This complements PR #6572 which handles the case where compressed SSE
events are lost/delayed, but does not cover the session switch scenario.
Root cause: loadSession() tears down approval/clarify/composer state but
missed the compression UI state, which is per-session and must not leak.
Fix: Clear compression state immediately after hideClarifyCard() in the
loadSession() teardown sequence.
happy5318
f7887bfc87
