feat(audio): podcast cover art in system Now Playing, CLI --play included

The cover was previously only wired through the UI hook; --play skipped it.
Also: Bun's fetch hangs in compiled binaries (Bun 1.3.8) — every cover
download silently failed in shipped builds, timing out against any host.
Cover staging now shells out to curl (present on macOS/Linux, 8s bound),
shared via src/utils/cover-art.ts so the UI and CLI paths stage the same
temp file and pass it to mpv as --cover-art-files (albumart track).

src/hooks/useAudio.ts

@@ -13,6 +13,8 @@
  */
 
 import { createSignal, onCleanup } from "solid-js";
+import { unlinkSync } from "fs";
+import { fetchCoverArt, coverTempPath } from "../utils/cover-art";
 import {
 	createAudioBackend,
 	detectPlayers,
@@ -109,6 +111,11 @@ function registerExitTeardown(): void {
 		} catch {
 			/* best-effort at exit */
 		}
+		try {
+			unlinkSync(coverTempPath());
+		} catch {
+			/* best-effort at exit */
+		}
 	};
 	process.on("exit", teardown);
 	for (const sig of ["SIGINT", "SIGTERM", "SIGHUP"] as const) {
@@ -173,6 +180,11 @@ function stopPolling(): void {
 	}
 }
 
+// ── Cover art for system Now Playing ─────────────────────────────────────────
+// macOS shows the media session's albumart in the audio center; mpv reads it
+// from `--cover-art-files`. Shared helper (utils/cover-art.ts) fetches the
+// podcast cover to a temp file BEFORE playback starts, bounded to 3s.
+
 async function play(episode: Episode): Promise<void> {
 	const b = ensureBackend();
 	setError(null);
@@ -192,6 +204,9 @@ async function play(episode: Episode): Promise<void> {
 		const feedStore = useFeedStore();
 		const feed = feedStore.feeds().find((f) => f.podcast.id === episode.podcastId);
 		const podcastTitle = feed?.customName || feed?.podcast.title || "";
+		const coverArtPath = feed?.podcast.coverUrl
+			? await fetchCoverArt(feed.podcast.coverUrl)
+			: null;
 
 		// Resume from saved progress if available and not completed
 		const savedProgress = progressStore.get(episode.id);
@@ -205,6 +220,7 @@ async function play(episode: Episode): Promise<void> {
 			speed: spd,
 			startPosition: startPos > 0 ? startPos : undefined,
 			mediaTitle: podcastTitle ? `${podcastTitle} — ${episode.title}` : episode.title,
+			coverArtPath: coverArtPath ?? undefined,
 		});
 
 		setCurrentEpisode(episode);
@@ -373,6 +389,9 @@ async function switchBackend(name: BackendName): Promise<void> {
 				.feeds()
 				.find((f) => f.podcast.id === ep.podcastId);
 			const podcastTitle = feed?.customName || feed?.podcast.title || "";
+			const coverArtPath = feed?.podcast.coverUrl
+				? await fetchCoverArt(feed.podcast.coverUrl)
+				: null;
 			await backend.play(ep.audioUrl, {
 				startPosition: pos,
 				volume: vol,
@@ -380,6 +399,7 @@ async function switchBackend(name: BackendName): Promise<void> {
 				mediaTitle: podcastTitle
 					? `${podcastTitle} — ${ep.title}`
 					: ep.title,
+				coverArtPath: coverArtPath ?? undefined,
 			});
 			setIsPlaying(true);
 			startPolling();

src/index.tsx

@@ -182,9 +182,18 @@ async function handlePlay(feeds: Feed[], arg: string): Promise<void> {
 
 	try {
 		const { createAudioBackend } = await import("./utils/audio-player")
+		const { fetchCoverArt } = await import("./utils/cover-art")
 		const backend = createAudioBackend()
 		if (episodeResult.audioUrl) {
-			await backend.play(episodeResult.audioUrl)
+			// Stage the podcast cover so the system Now Playing shows
+			// artwork (mpv --cover-art-files), like the UI path does.
+			const coverArtPath = feedResult.podcast.coverUrl
+				? await fetchCoverArt(feedResult.podcast.coverUrl)
+				: null
+			await backend.play(episodeResult.audioUrl, {
+				mediaTitle: `${feedResult.podcast.title} — ${episodeResult.title}`,
+				coverArtPath: coverArtPath ?? undefined,
+			})
 			console.log("Playback started (use the UI to control)")
 		} else {
 			console.log("No audio URL available for this episode")

src/utils/cover-art.ts

@@ -0,0 +1,57 @@
+/**
+ * Cover-art staging for the system Now Playing session.
+ *
+ * macOS shows the media session's albumart in the audio center (Control
+ * Center / lock screen). mpv reads it from `--cover-art-files` (loads the
+ * file as an albumart video track), so the podcast cover is staged to a temp
+ * file BEFORE playback starts and passed to mpv.
+ *
+ * Downloaded via `curl` (not `fetch`): Bun's `fetch` hangs in compiled
+ * `bun build --compile` binaries (Bun 1.3.8), timing out on any host —
+ * which would silently drop every cover in shipped builds. curl is present
+ * on macOS and Linux. Bounded: a slow cover server must never stall audio,
+ * so an 8s cap drops the art.
+ */
+
+import { tmpdir } from "os";
+import { join } from "path";
+import { unlinkSync, statSync } from "fs";
+
+export const coverTempPath = () => join(tmpdir(), "podtui-cover.jpg");
+
+export async function fetchCoverArt(url: string): Promise<string | null> {
+	const path = coverTempPath();
+	try {
+		unlinkSync(path);
+	} catch {
+		/* no stale cover */
+	}
+	try {
+		return await Promise.race([
+			(async () => {
+				const proc = Bun.spawn([
+					"curl",
+					"-sS",
+					"--fail",
+					"-m",
+					"8",
+					"--max-filesize",
+					"2097152",
+					"-o",
+					path,
+					url,
+				]);
+				const code = await proc.exited;
+				if (code !== 0) return null;
+				try {
+					return statSync(path).size > 0 ? path : null;
+				} catch {
+					return null;
+				}
+			})(),
+			new Promise<null>((resolve) => setTimeout(() => resolve(null), 8000)),
+		]);
+	} catch {
+		return null;
+	}
+}