feat(audit): Batch 23 — settings key renames with migration (CC1) + config.ts (CC11)

CC1: customCommandEnabled→enableCustomCommands, downloadArchive→
useDownloadArchive, clipboardWatch→watchClipboard, sidebarCollapsed→
isSidebarCollapsed, hardwareAcceleration→useHardwareAcceleration,
videoDir/audioDir→videoFolder/audioFolder (+ chooseDir/clearDir store
actions → chooseFolder/clearFolder). Rename map in settingsMigration.ts
(pure, unit-tested incl. pre-rename backup fixture), applied as an
idempotent on-disk shim at store open and on backup import so old
settings.json and old backups both keep working.

CC11: update host/owner/repo + release API moved to src/main/config.ts.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/main/index.ts

@@ -44,7 +44,7 @@ setupPortableData()
 // safe default; users on modern GPUs can flip Settings → Appearance →
 // "Hardware acceleration" (applies on next launch — this must run before the
 // app is ready). The window backgroundColor is theme-matched (see createWindow).
-if (!getSettings().hardwareAcceleration) {
+if (!getSettings().useHardwareAcceleration) {
   app.disableHardwareAcceleration()
 }
 // Native window-occlusion tracking stays off in BOTH modes — it's a separate