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/terminal.ts

@@ -3,7 +3,7 @@
  * arguments and streams stdout/stderr back to the renderer line-by-line.
  *
  * SECURITY: the executable is fixed to the managed yt-dlp (never an arbitrary exe),
- * and the whole feature is gated on Settings.customCommandEnabled — the same consent
+ * and the whole feature is gated on Settings.enableCustomCommands — the same consent
  * flag that guards per-download extra args, because yt-dlp args can run arbitrary
  * code (`--exec`). The gate is enforced here in main, not just in the renderer UI.
  */
@@ -25,7 +25,7 @@ function send(wc: WebContents, ev: TerminalEvent): void {
 }
 
 export function runTerminal(wc: WebContents, id: string, argsRaw: string): TerminalRunResult {
-  if (!getSettings().customCommandEnabled) {
+  if (!getSettings().enableCustomCommands) {
     return {
       ok: false,
       error: 'Enable "Run custom commands" in Settings → Custom commands to use the terminal.'