009: Polish bacon fixes, OTA host scripts, and migration docs.

Restore disable_configstore, EuiccDisabler and thermal CDEV guards, branding
and rebuild/sync helpers; document device roles, laptop migration, and Gitea.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/session-20260916-handoff.md

@@ -1,3 +1,7 @@
+<!-- Status: parallel KernelSU track — see docs/007-parallel-on-009.md -->
+
+> **Status: parallel KernelSU / SusFS track** (kept). Bridge to current Magisk ROM: [`007-parallel-on-009.md`](007-parallel-on-009.md). Magisk ship resume: [`009-handoff-20261008.md`](009-handoff-20261008.md).
+
 # Session handoff — 2026-09-16 (LAB / 007)
 
 **For the next chat:** read this file first, then `docs/007-kernelsu-runbook.md`.