feat(frontend): add ShowTile, SeasonTile, BreadcrumbNav components

k-tv-frontend/app/(main)/library/components/breadcrumb-nav.tsx

@@ -0,0 +1,41 @@
+interface Props {
+  series?: string;
+  season?: number;
+  onNavigate: (target: "root" | "series") => void;
+}
+
+export function BreadcrumbNav({ series, season, onNavigate }: Props) {
+  return (
+    <nav className="flex items-center gap-1 px-1 py-2 text-sm">
+      <button
+        type="button"
+        className="text-zinc-400 hover:text-zinc-100 transition-colors"
+        onClick={() => onNavigate("root")}
+      >
+        Library
+      </button>
+      {series && (
+        <>
+          <span className="text-zinc-600">›</span>
+          {season != null ? (
+            <button
+              type="button"
+              className="text-zinc-400 hover:text-zinc-100 transition-colors"
+              onClick={() => onNavigate("series")}
+            >
+              {series}
+            </button>
+          ) : (
+            <span className="text-zinc-100">{series}</span>
+          )}
+        </>
+      )}
+      {season != null && (
+        <>
+          <span className="text-zinc-600">›</span>
+          <span className="text-zinc-100">Season {season}</span>
+        </>
+      )}
+    </nav>
+  );
+}