Fix L29/L52: QUALITY_OPTIONS moved to UI module; installer spawn via child_process

L29: QUALITY_OPTIONS was a presentational constant living in store/downloads.ts,
     coupling views to the store. Moved to src/renderer/src/qualityOptions.ts,
     which assembles it directly from @shared/ipc. store/downloads.ts no longer
     imports VIDEO/AUDIO_QUALITY_OPTIONS. Both consumers (DownloadBar, SettingsView)
     updated to import from the new module.

L52: Replaced the fixed `setTimeout(app.quit, 1500)` installer handoff with a
     detached spawn. The installer is spawned with stdio:'ignore' and unref'd so
     it outlives AeroFetch even on a slow machine. app.quit() fires on setImmediate
     so the IPC response returns to the renderer before the process exits.

typecheck + 242 tests green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/renderer/src/components/DownloadBar.tsx

@@ -28,7 +28,8 @@ import {
   WarningRegular
 } from '@fluentui/react-icons'
 import type { MediaInfo, FormatOption, PlaylistInfo } from '@shared/ipc'
-import { useDownloads, QUALITY_OPTIONS, type MediaKind } from '../store/downloads'
+import { useDownloads, type MediaKind } from '../store/downloads'
+import { QUALITY_OPTIONS } from '../qualityOptions'
 import { sameVideo } from '../store/queueStats'
 import { useSettings } from '../store/settings'
 import { Select } from './Select'

src/renderer/src/components/SettingsView.tsx

@@ -55,7 +55,8 @@ import {
 } from '@shared/ipc'
 import { useSettings } from '../store/settings'
 import { useSystemTheme } from '../store/systemTheme'
-import { QUALITY_OPTIONS, useDownloads } from '../store/downloads'
+import { useDownloads } from '../store/downloads'
+import { QUALITY_OPTIONS } from '../qualityOptions'
 import { useTemplates } from '../store/templates'
 import { useErrorLog } from '../store/errorlog'
 import { Select } from './Select'

src/renderer/src/qualityOptions.ts

@@ -0,0 +1,6 @@
+import { VIDEO_QUALITY_OPTIONS, AUDIO_QUALITY_OPTIONS } from '@shared/ipc'
+
+export const QUALITY_OPTIONS = {
+  video: VIDEO_QUALITY_OPTIONS,
+  audio: AUDIO_QUALITY_OPTIONS
+} as const

src/renderer/src/store/downloads.ts

@@ -1,7 +1,5 @@
 import { create } from 'zustand'
 import {
-  VIDEO_QUALITY_OPTIONS,
-  AUDIO_QUALITY_OPTIONS,
   type DownloadEvent,
   type DownloadMeta,
   type DownloadOptions,
@@ -71,13 +69,6 @@ export interface DownloadItem {
   mediaItemId?: string
 }
 
-// `satisfies` (not an annotation) so the tuple element types survive: under
-// noUncheckedIndexedAccess a `readonly string[]` index yields `string | undefined`,
-// but the const tuples keep `QUALITY_OPTIONS[kind][0]` known-defined (L168).
-export const QUALITY_OPTIONS = {
-  video: VIDEO_QUALITY_OPTIONS,
-  audio: AUDIO_QUALITY_OPTIONS
-} satisfies Record<MediaKind, readonly string[]>
 
 // Placeholder channel shown while metadata is still being fetched. Tracked as a
 // constant so the meta/error/done handlers can recognise and clear it instead of