revert(macos): drop PodTui.app / bundled-mpv Now Playing attribution

The pinned mpv binary breaks on brew ffmpeg major drift (libavcodec.62 vs
.63 shipped a dead player); making it self-contained costs ~100MB for an
app icon. Removing the whole machinery: build.ts app-bundle assembly,
audio-player bundled-binary resolver + probe (spawns PATH mpv again),
CI mpv install + bundle smoke checks, AppIcon.icns, README note.
Cover-art staging (curl + --cover-art-files) is unrelated and stays.

build.ts

@@ -131,130 +131,6 @@ if (COMPILE) {
 		}
 	}
 
-	// macOS app bundle: PodTui.app. We run our audio backend (mpv) from
-	// INSIDE the bundle (Contents/MacOS/mpv) so macOS attributes its Now
-	// Playing session to PodTui — the source-app icon + name in Control
-	// Center / lock screen — instead of a blank placeholder for an
-	// unbundled binary. AudioPlayer's resolver prefers this sibling.
-	if (platform === "darwin") {
-		const appRoot = join(tarRoot, "PodTui.app");
-		const macosDir = join(appRoot, "Contents", "MacOS");
-		const resDir = join(appRoot, "Contents", "Resources");
-		mkdirSync(macosDir, { recursive: true });
-		mkdirSync(resDir, { recursive: true });
-
-		copyFileSync(outfile, join(macosDir, "podtui"));
-		for (const lib of [`libopentui.${libExt}`, cavacoreLib]) {
-			const s = join("dist", lib);
-			if (existsSync(s)) copyFileSync(s, join(macosDir, lib));
-		}
-
-		const mpvResolve = Bun.spawnSync(["which", "mpv"]);
-		const mpvPath =
-			mpvResolve.exitCode === 0 ? mpvResolve.stdout.toString().trim() : "";
-		if (mpvPath) {
-			copyFileSync(mpvPath, join(macosDir, "mpv"));
-		} else {
-			// A darwin release tarball without a bundled mpv silently ships
-			// without Now Playing attribution (blank icon). Fail loudly so CI
-			// can't produce it — the runner must have mpv installed.
-			console.error(
-				"Error: mpv not found in PATH — PodTui.app requires a bundled mpv for macOS Now Playing attribution (brew install mpv on the build machine)",
-			);
-			process.exit(1);
-		}
-
-		const icnsSrc = join("assets", "App Icon", "AppIcon.icns");
-		if (existsSync(icnsSrc)) {
-			copyFileSync(icnsSrc, join(resDir, "AppIcon.icns"));
-		} else {
-			console.warn(
-				"Warning: assets/App Icon/AppIcon.icns missing — app bundle has no icon",
-			);
-		}
-
-		// Version for the bundle comes from src/index.tsx (single source of
-		// truth — release.yml requires bumping it in the tag commit).
-		const srcIndex = await Bun.file(join("src", "index.tsx")).text();
-		const versionMatch = srcIndex.match(/const VERSION = "([^"]+)"/);
-		const bundleVersion = versionMatch?.[1];
-		if (!bundleVersion) {
-			console.error("Error: could not read VERSION from src/index.tsx");
-			process.exit(1);
-		}
-
-		Bun.write(
-			join(appRoot, "Contents", "Info.plist"),
-			`<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-<dict>
-	<key>CFBundleName</key>
-	<string>PodTui</string>
-	<key>CFBundleDisplayName</key>
-	<string>PodTui</string>
-	<key>CFBundleIdentifier</key>
-	<string>com.mikefreno.podtui</string>
-	<key>CFBundleExecutable</key>
-	<string>podtui</string>
-	<key>CFBundlePackageType</key>
-	<string>APPL</string>
-	<key>CFBundleIconFile</key>
-	<string>AppIcon</string>
-	<key>CFBundleShortVersionString</key>
-	<string>${bundleVersion}</string>
-	<key>CFBundleVersion</key>
-	<string>${bundleVersion}</string>
-	<key>LSMinimumSystemVersion</key>
-	<string>12.0</string>
-</dict>
-</plist>
-`,
-		);
-
-		// Ad-hoc sign so the bundle launches cleanly on fresh machines.
-		// Identity overridable via PODTUI_CODESIGN_IDENTITY (e.g. a Developer
-		// ID cert for release builds); default ad-hoc.
-		const signIdentity = process.env.PODTUI_CODESIGN_IDENTITY || "-";
-		const sign = Bun.spawnSync([
-			"codesign",
-			"--force",
-			"--deep",
-			"-s",
-			signIdentity,
-			appRoot,
-		]);
-		if (sign.exitCode !== 0) {
-			console.warn(
-				`Warning: codesign failed (${sign.stderr.toString().trim()}) — app bundle unsigned`,
-			);
-		}
-
-		// Sign the nested mpv LAST with our bundle identifier. mediaremoted
-		// resolves the Now Playing client from the registering process's
-		// code-signing identifier — without an explicit --identifier codesign
-		// stamps "mpv" (its basename) and the audio center shows a blank
-		// placeholder. Must run after the bundle sign above (a later bundle
-		// re-seal would re-derive the basename identifier).
-		const signMpv = Bun.spawnSync([
-			"codesign",
-			"--force",
-			"-s",
-			signIdentity,
-			"--identifier",
-			"com.mikefreno.podtui",
-			join(macosDir, "mpv"),
-		]);
-		if (signMpv.exitCode !== 0) {
-			console.warn(
-				`Warning: nested mpv signing failed (${signMpv.stderr
-					.toString()
-					.trim()}) — Now Playing attribution won't work`,
-			);
-		}
-		console.log(`App bundle: ${appRoot}`);
-	}
-
 	const tar = Bun.spawnSync([
 		"tar",
 		"-czf",