add version badge in nav, apply path mappings at execution time, clear done/error jobs

- show version (from package.json) in nav bar, warn on frontend/server mismatch
- apply path_mappings to file access check and command string at execution time
  so existing scans with old jellyfin paths work without re-scanning
- add clear done/errors button on execute page
- bump version to 2026.03.04

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/routes/__root.tsx

@@ -1,5 +1,9 @@
 import { createRootRoute, Link, Outlet } from '@tanstack/react-router';
+import { useEffect, useState } from 'react';
 import { cn } from '~/shared/lib/utils';
+import { api } from '~/shared/lib/api';
+
+declare const __APP_VERSION__: string;
 
 export const Route = createRootRoute({
 	component: RootLayout,
@@ -17,6 +21,19 @@ function NavLink({ to, children }: { to: string; children: React.ReactNode }) {
 	);
 }
 
+function VersionBadge() {
+	const [serverVersion, setServerVersion] = useState<string | null>(null);
+	useEffect(() => { api.get<{ version: string }>('/api/version').then((d) => setServerVersion(d.version)).catch(() => {}); }, []);
+	const buildVersion = typeof __APP_VERSION__ !== 'undefined' ? __APP_VERSION__ : null;
+	const mismatch = buildVersion && serverVersion && buildVersion !== serverVersion;
+	return (
+		<span className="text-[0.65rem] text-gray-400 font-mono ml-1" title={mismatch ? `Frontend: ${buildVersion}, Server: ${serverVersion}` : undefined}>
+			v{serverVersion ?? buildVersion ?? '?'}
+			{mismatch && <span className="text-amber-500 ml-1" title="Frontend and server versions differ — rebuild or refresh">⚠</span>}
+		</span>
+	);
+}
+
 function RootLayout() {
 	const isDev = import.meta.env.DEV;
 	return (
@@ -30,6 +47,7 @@ function RootLayout() {
 				<Link to="/" className="font-bold text-[0.95rem] mr-5 no-underline text-gray-900">
 					🎬 netfelix-audio-fix
 				</Link>
+				<VersionBadge />
 				<NavLink to="/scan">Scan</NavLink>
 				<NavLink to="/review/audio">Audio</NavLink>
 				<NavLink to="/review/subtitles">Subtitles</NavLink>