Add IR remote control (LIRC) with a number-key content mapping

Adds a TCP client for lircd's classic protocol: play/pause/next/prev/
volume/mute map to the same intents every other front-end already
emits, and number keys 0-9 play an assigned album/audiobook from the
start or a podcast show's newest episode, resolved fresh on every
press. The mapping is configured in config.yml and editable from the
frontend: a small "Taste zuweisen" button on the play screen (or the
A+digit keyboard shortcut) opens a 10-key picker to assign whatever is
currently playing.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/components/PlayView.tsx

@@ -21,6 +21,10 @@ interface Props {
   onMute: () => void;
   onBrowse: () => void;
   onOpenAlbum: () => void;
+  /** Assigning the current album/show to a remote key. `assignPending` is true right
+   * after "A" is pressed, waiting for the digit that completes the shortcut. */
+  onOpenAssign: () => void;
+  assignPending: boolean;
 }
 
 export function PlayView({
@@ -34,6 +38,8 @@ export function PlayView({
   onMute,
   onBrowse,
   onOpenAlbum,
+  onOpenAssign,
+  assignPending,
 }: Props) {
   const position = usePlaybackClock(state.position, state.playing);
   const book = album ? isBook(album) : false;
@@ -245,6 +251,32 @@ export function PlayView({
           </span>
           Zurück zur Suche
         </button>
+
+        {album && (
+          <button
+            onClick={onOpenAssign}
+            title="Einer Fernbedienungs-Taste zuweisen (oder: A und dann eine Zahl)"
+            style={{
+              position: "absolute",
+              top: 28,
+              right: 84,
+              border: "none",
+              cursor: "pointer",
+              background: assignPending ? "var(--accent)" : "oklch(97% 0.01 210 / .95)",
+              borderRadius: 999,
+              padding: "11px 20px",
+              fontSize: 14,
+              fontWeight: 800,
+              color: assignPending ? "#fff" : "var(--ink)",
+              display: "flex",
+              alignItems: "center",
+              gap: 8,
+              boxShadow: "0 8px 24px oklch(15% 0.05 210 / .4)",
+            }}
+          >
+            🎛️ {assignPending ? "Zahl drücken …" : "Taste zuweisen"}
+          </button>
+        )}
       </div>
     </div>
   );