Adds the new shows admin screen and drives schedule from it

src/styles/_mixins.scss

@@ -104,3 +104,50 @@
   0%, 100% { transform: translateY(0); }
   50%      { transform: translateY(-8px); }
 }
+
+// ── URL field with upload button ──────────────────────────────
+
+@mixin url-with-upload {
+  .url-with-upload {
+    display: flex;
+    gap: $spacing-sm;
+    align-items: center;
+
+    input[type="text"] {
+      flex: 1;
+    }
+  }
+
+  .btn-upload {
+    position: relative;
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    background: $neutral-light;
+    color: $neutral-dark;
+    border: none;
+    border-radius: $radius-md;
+    padding: $spacing-sm $spacing-md;
+    font-size: 0.875rem;
+    cursor: pointer;
+    transition: background $transition-fast;
+    white-space: nowrap;
+
+    &:hover {
+      background: $neutral-medium;
+      color: $neutral-white;
+    }
+
+    input[type="file"] {
+      position: absolute;
+      inset: 0;
+      opacity: 0;
+      cursor: pointer;
+      width: 100%;
+
+      &:disabled {
+        cursor: not-allowed;
+      }
+    }
+  }
+}