Merge feat/documents-folders-and-ui: Documents folders, collapsible sidebar, theme switch

# Conflicts:
#	src/main/download.ts
#	src/renderer/src/components/DownloadBar.tsx

src/shared/ipc.ts

@@ -4,6 +4,8 @@
  */
 
 export const IpcChannels = {
+  /** the AeroFetch app version (package.json / app.getVersion) */
+  appVersion: 'app:version',
   ytdlpVersion: 'ytdlp:version',
   probe: 'media:probe',
   downloadStart: 'download:start',
@@ -355,8 +357,10 @@ export type DownloadEvent =
 
 /** Persisted user settings (electron-store). */
 export interface Settings {
-  /** absolute output directory (empty string resolves to the OS Downloads folder) */
-  outputDir: string
+  /** where video downloads are saved; empty string = the default Documents\Video folder */
+  videoDir: string
+  /** where audio downloads are saved; empty string = the default Documents\Audio folder */
+  audioDir: string
   defaultKind: MediaKind
   defaultVideoQuality: string
   defaultAudioQuality: string