Add Pinchflat-style media manager: index channels into playlist folders

Index an entire YouTube channel or playlist once, then download it into
organized <Channel>/<Playlist>/<NNN> - <Title> folders, with incremental
re-sync. Built in six rebuild-gated phases (F-K); see ROADMAP-PINCHFLAT.md.

- F: channel-walk indexer (/playlists + /videos) -> persisted Source +
  MediaItem JSON stores; pure classify/dedup logic in indexerCore.ts
- G: Windows-safe folder paths + dir sanitizer (collectionOutputTemplate)
- H: Library tab + source tree + "Download pending" into the existing queue
- I: state-preserving re-index merge + persist-downloaded-on-complete
- J: watched sources, RSS fast-check, Task Scheduler + --sync launch
  (the OS-level scheduling/RSS need a real-install smoke test)
- K: .info.json / thumbnail / .description sidecars for media servers

Also gitignore .gitea-token. 106 unit tests pass; typecheck + build clean.

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

test/buildArgs.test.ts

@@ -3,6 +3,8 @@ import {
   buildArgs,
   parseExtraArgs,
   formatCommandLine,
+  sanitizeDirSegment,
+  collectionOutputTemplate,
   CROP_SQUARE_PPA,
   ARIA2C_ARGS,
   type AccessOptions
@@ -360,3 +362,91 @@ describe('buildArgs extraArgs', () => {
     expect(withEmpty).toEqual(withoutParam)
   })
 })
+
+// --- Media-server sidecar files (Phase K) -----------------------------------
+
+describe('sidecar files', () => {
+  it('emits --write-info-json / --write-thumbnail / --write-description when enabled', () => {
+    const argv = build(
+      opts(),
+      dlo({ writeInfoJson: true, writeThumbnailFile: true, writeDescription: true })
+    )
+    expect(argv).toContain('--write-info-json')
+    expect(argv).toContain('--write-thumbnail')
+    expect(argv).toContain('--write-description')
+  })
+
+  it('emits none of them by default', () => {
+    const argv = build(opts(), dlo())
+    expect(argv).not.toContain('--write-info-json')
+    expect(argv).not.toContain('--write-description')
+    // (--write-thumbnail is sidecar-only here; embedThumbnail uses --embed-thumbnail)
+    expect(argv).not.toContain('--write-thumbnail')
+  })
+})
+
+// --- Collection folder paths (Phase G, media-manager) -----------------------
+
+describe('sanitizeDirSegment', () => {
+  it('keeps an ordinary name (incl. spaces and hyphens) intact', () => {
+    expect(sanitizeDirSegment('Linus Tech Tips')).toBe('Linus Tech Tips')
+    expect(sanitizeDirSegment('Two-Minute Papers')).toBe('Two-Minute Papers')
+  })
+
+  it('replaces Windows-illegal characters with a space and collapses runs', () => {
+    expect(sanitizeDirSegment('A/B\\C:D*E?F')).toBe('A B C D E F')
+    expect(sanitizeDirSegment('Best of 2024 <Live>')).toBe('Best of 2024 Live')
+  })
+
+  it('strips leading/trailing dots and spaces, neutralising `..` traversal', () => {
+    expect(sanitizeDirSegment('..')).toBe('Untitled')
+    expect(sanitizeDirSegment('../../etc')).toBe('etc')
+    expect(sanitizeDirSegment('  trailing.  ')).toBe('trailing')
+    expect(sanitizeDirSegment('My Playlist.')).toBe('My Playlist')
+  })
+
+  it('prefixes reserved Windows device names', () => {
+    expect(sanitizeDirSegment('CON')).toBe('_CON')
+    expect(sanitizeDirSegment('com1')).toBe('_com1')
+  })
+
+  it('falls back to Untitled for empty / all-illegal input', () => {
+    expect(sanitizeDirSegment('')).toBe('Untitled')
+    expect(sanitizeDirSegment('???')).toBe('Untitled')
+  })
+
+  it('caps length to keep the overall path bounded', () => {
+    expect(sanitizeDirSegment('x'.repeat(200)).length).toBe(80)
+  })
+})
+
+describe('collectionOutputTemplate', () => {
+  const ctx = { channel: 'DevChannel', playlist: 'Full Course', index: 3 }
+
+  it('files into <out>/<channel>/<playlist>/<NNN> - <filename>', () => {
+    const t = collectionOutputTemplate('C:/out', ctx, '%(title)s.%(ext)s')
+    // normalise separators so the assertion is OS-independent
+    expect(t.replace(/\\/g, '/')).toBe('C:/out/DevChannel/Full Course/003 - %(title)s.%(ext)s')
+  })
+
+  it('zero-pads the index to three digits and clamps bad values to 001', () => {
+    expect(collectionOutputTemplate('C:/o', { ...ctx, index: 42 }, 'f').replace(/\\/g, '/')).toContain(
+      '/042 - f'
+    )
+    expect(collectionOutputTemplate('C:/o', { ...ctx, index: 0 }, 'f').replace(/\\/g, '/')).toContain(
+      '/001 - f'
+    )
+    expect(
+      collectionOutputTemplate('C:/o', { ...ctx, index: NaN }, 'f').replace(/\\/g, '/')
+    ).toContain('/001 - f')
+  })
+
+  it('sanitizes the channel and playlist folder names', () => {
+    const t = collectionOutputTemplate(
+      'C:/out',
+      { channel: 'A/B', playlist: '..', index: 1 },
+      '%(title)s.%(ext)s'
+    )
+    expect(t.replace(/\\/g, '/')).toBe('C:/out/A B/Untitled/001 - %(title)s.%(ext)s')
+  })
+})