feat(pinchflat): Media Profiles — named download presets per Library source

A MediaProfile bundles { kind, quality, options, outputTemplate, extraArgs }
that a Source points at via Source.profileId, overriding the global defaults
field-by-field for that source's downloads.

Backend mirrors CommandTemplate: profiles.ts (createJsonStore, PROFILES_MAX,
isProfileLike + sanitize), CRUD IPC (profiles:list/save/remove) + preload +
useProfiles store; Source.profileId + sources:set-profile. Pure resolution
in @shared/profileResolve.ts (profile → global, per field; unit-tested).
Applied in the sources-store enqueueItems; a per-download collectionOutput-
Template override threads to buildArgs so a profile's outputTemplate wins.

UI: ProfileManager (mirrors TemplateManager) in a new Settings → Advanced →
Media profiles card, plus a per-source Profile picker in the Library source
detail. Both live-verified in the preview; 354 tests pass.

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

src/shared/ipc.ts

@@ -42,6 +42,10 @@ export const IpcChannels = {
   templatesList: 'templates:list',
   templatesSave: 'templates:save',
   templatesRemove: 'templates:remove',
+  /** Media profiles: named download presets a Source can point at (PINCHFLAT) */
+  profilesList: 'profiles:list',
+  profilesSave: 'profiles:save',
+  profilesRemove: 'profiles:remove',
   commandPreview: 'command:preview',
   ytdlpUpdate: 'ytdlp:update',
   /** main → renderer push channel for background yt-dlp auto-update status */
@@ -78,6 +82,8 @@ export const IpcChannels = {
   sourceItemDownloaded: 'sources:item-downloaded',
   /** toggle whether a source is watched for new uploads (Phase J) */
   sourceSetWatched: 'sources:set-watched',
+  /** point a source at a MediaProfile (or clear it) */
+  sourceSetProfile: 'sources:set-profile',
   /** re-index all watched sources and return the videos that are new */
   sourcesSync: 'sources:sync',
   /** get / set the Windows scheduled-sync task (Task Scheduler) */
@@ -476,6 +482,12 @@ export interface StartDownloadOptions {
    * filenameTemplate. See CollectionContext.
    */
   collection?: CollectionContext
+  /**
+   * Per-download collection folder-layout override (a Media Profile's
+   * `outputTemplate`). When set, it overrides `Settings.collectionOutputTemplate`
+   * for this collection download; omit to fall back to the global setting.
+   */
+  collectionOutputTemplate?: string
 }
 
 export interface StartDownloadResult {
@@ -847,6 +859,31 @@ export interface Source {
   watched?: boolean
   /** YouTube RSS feed URL for cheap "anything new?" checks; undefined if unknown */
   feedUrl?: string
+  /** id of the MediaProfile applied to this source's downloads; undefined = global defaults */
+  profileId?: string
+}
+
+/**
+ * A named download preset a Library Source can point at (PINCHFLAT "Media
+ * Profile"): a reusable bundle of the per-download choices that would otherwise
+ * come from the global defaults — kind, quality, post-processing options, the
+ * collection folder layout, and extra yt-dlp args. A Source with a `profileId`
+ * resolves those fields from the profile first, then falls back to the global
+ * settings for any field the profile leaves unset (see resolveProfile).
+ */
+export interface MediaProfile {
+  id: string
+  name: string
+  /** override the download kind (video/audio); unset = global default */
+  kind?: MediaKind
+  /** override the quality label ('1080p', 'Best', …); unset = global default */
+  quality?: string
+  /** override post-processing options; unset = global default */
+  options?: DownloadOptions
+  /** override the collection folder layout (raw yt-dlp -o template); unset = global default */
+  outputTemplate?: string
+  /** extra yt-dlp args appended to the argv (like a CommandTemplate's args); unset = none */
+  extraArgs?: string
 }
 
 /**

src/shared/profileResolve.ts

@@ -0,0 +1,51 @@
+import type { MediaProfile, MediaKind, DownloadOptions } from './ipc'
+
+/**
+ * The global defaults a Media Profile can override — exactly the fields a
+ * collection download would otherwise pull from Settings.
+ */
+export interface ProfileDefaults {
+  kind: MediaKind
+  videoQuality: string
+  audioQuality: string
+  options: DownloadOptions
+  /** Settings.collectionOutputTemplate — the global collection folder layout */
+  outputTemplate: string
+}
+
+/** The resolved per-download values a Source's profile (or the globals) produce. */
+export interface ResolvedProfile {
+  kind: MediaKind
+  quality: string
+  options: DownloadOptions
+  /** collection folder layout ('' = the built-in default), or the profile override */
+  outputTemplate: string
+  /** extra yt-dlp args from the profile ('' when none) */
+  extraArgs: string
+}
+
+/**
+ * Resolve a download's effective settings for a Library source: **profile →
+ * global default**, field by field. A `null`/`undefined` profile (source not
+ * pointed at one, or a dangling id) yields the pure global defaults. The quality
+ * default follows the resolved kind, so an audio-kind profile without its own
+ * quality picks up the global AUDIO default (not video).
+ *
+ * Lives in `@shared` because both the renderer's enqueue path (which needs the
+ * resolved kind/quality for the queued item) and any main-side use share this
+ * one precedence rule. Pure — unit-tested in test/profileResolve.test.ts.
+ */
+export function resolveProfile(
+  profile: MediaProfile | null | undefined,
+  defaults: ProfileDefaults
+): ResolvedProfile {
+  const kind = profile?.kind ?? defaults.kind
+  const globalQuality = kind === 'audio' ? defaults.audioQuality : defaults.videoQuality
+  return {
+    kind,
+    quality: profile?.quality ?? globalQuality,
+    options: profile?.options ?? defaults.options,
+    outputTemplate: profile?.outputTemplate ?? defaults.outputTemplate,
+    extraArgs: profile?.extraArgs ?? ''
+  }
+}