Fix H5/H6/M21/L37-40/L47/L55/L68/L72/L76/L91/L98/L108/L165/L166 audit items

H5: HistoryEntry now stores formatId+formatHasAudio; redownload passes them
    back to addFromUrl so the original yt-dlp format is reused, not guessed.
    Compound quality labels stripped to the preset prefix for old history.
L72: thumbnail now passed in redownload so re-queued rows keep their art.
H6: TerminalView log capped at MAX_LOG_LINES=2000 to prevent unbounded growth.
M21: --audio-quality omitted for lossless audioFormats (flac/wav).
L166: fmtEta hour rollover fixed in all 3 locations -- 2h00:00 not 120:00.
L165: queueStats formatSpeed precision aligned with fmtBytes.
L55: QueueItem suppresses sizeLabel when already in probed-format quality label.
L47: probeMeta null sends empty meta event so Resolving clears via SR6.
L68: notifiedBackground resets on window show for subsequent close-while-downloading.
L76: dup warning falls back to URL when title is still a placeholder.
L91: SettingsView onFormatSelect uses indexOf instead of unsafe tuple cast.
L98: Embed chapters field gets a hint text.
L108: BrowserWindow created with explicit title AeroFetch.
L37: pure formatters extracted to src/main/lib/formatters.ts and unit-tested.
L38: buildArgs test covers webm thumbnail suppression.
L39: CROP_SQUARE_PPA test is structural not exact-string.
L40: looksLikeUrl/looksLikeSingleVideo extracted to src/renderer/src/lib/urlHelpers.ts.

typecheck + 242 tests + eslint + prettier green.

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

src/main/lib/formatters.ts

@@ -0,0 +1,57 @@
+import type { DownloadProgress } from '@shared/ipc'
+
+// Pure formatting helpers for yt-dlp progress output. Extracted from download.ts
+// so they can be unit-tested without pulling in the electron import chain (L37).
+
+function num(s?: string): number | undefined {
+  if (!s || s === 'NA') return undefined
+  const n = Number(s)
+  return Number.isFinite(n) ? n : undefined
+}
+
+export function fmtBytes(bytes: number): string {
+  if (bytes < 1024) return `${bytes} B`
+  const units = ['KB', 'MB', 'GB', 'TB']
+  let v = bytes / 1024
+  let i = 0
+  while (v >= 1024 && i < units.length - 1) {
+    v /= 1024
+    i++
+  }
+  return `${v.toFixed(v >= 100 ? 0 : 1)} ${units[i]}`
+}
+
+function fmtSpeed(bytesPerSec?: number): string | undefined {
+  if (bytesPerSec == null) return undefined
+  return `${fmtBytes(bytesPerSec)}/s`
+}
+
+export function fmtEta(seconds?: number): string | undefined {
+  if (seconds == null) return undefined
+  const s = Math.max(0, Math.round(seconds))
+  const h = Math.floor(s / 3600)
+  const m = Math.floor((s % 3600) / 60)
+  const r = s % 60
+  if (h > 0) return `${h}:${String(m).padStart(2, '0')}:${String(r).padStart(2, '0')}`
+  return `${m}:${String(r).padStart(2, '0')}`
+}
+
+export function parseProgress(rest: string): DownloadProgress | null {
+  const parts = rest.split('|')
+  if (parts.length < 6) return null
+  const [status, dl, total, totalEst, speed, eta] = parts
+  const downloaded = num(dl)
+  const totalBytes = num(total) ?? num(totalEst)
+  let progress = 0
+  if (totalBytes && downloaded != null) progress = Math.min(1, downloaded / totalBytes)
+  return {
+    status: status || 'downloading',
+    progress,
+    speed: fmtSpeed(num(speed)),
+    eta: fmtEta(num(eta)),
+    sizeLabel: totalBytes ? fmtBytes(totalBytes) : undefined,
+    // No (estimated) total → the % can never advance; flag it so the renderer
+    // shows an indeterminate bar rather than a stuck 0% (L137).
+    sizeUnknown: !totalBytes
+  }
+}