fix: double-paste bug, show actual yt-dlp errors in UI

Co-authored-by: Cursor <cursoragent@cursor.com>

src/lib/components/UrlInput.svelte

@@ -33,32 +33,40 @@
   function handlePaste(e: ClipboardEvent) {
     const text = e.clipboardData?.getData('text')?.trim();
     if (text && (text.startsWith('http://') || text.startsWith('https://'))) {
+      e.preventDefault();
       inputValue = text;
       setTimeout(handleSubmit, 50);
     }
   }
 </script>
 
-<div class="url-input">
-  <input
-    type="text"
-    placeholder="Paste a video URL and press Enter…"
-    bind:value={inputValue}
-    onkeydown={handleKeydown}
-    onpaste={handlePaste}
-    disabled={session.status === 'resolving'}
-  />
-  {#if session.status === 'resolving'}
-    <span class="spinner">⏳</span>
-  {/if}
+<div class="url-input-wrapper">
+  <div class="url-input">
+    <input
+      type="text"
+      placeholder="Paste a video URL and press Enter…"
+      bind:value={inputValue}
+      onkeydown={handleKeydown}
+      onpaste={handlePaste}
+      disabled={session.status === 'resolving'}
+    />
+    {#if session.status === 'resolving'}
+      <span class="spinner">⏳</span>
+    {/if}
+  </div>
   {#if session.error}
-    <span class="error" title={session.error}>⚠</span>
+    <div class="error-bar" title={session.error}>⚠ {session.error}</div>
   {/if}
 </div>
 
 <style>
-  .url-input {
+  .url-input-wrapper {
     flex: 1;
+    display: flex;
+    flex-direction: column;
+    gap: 4px;
+  }
+  .url-input {
     display: flex;
     align-items: center;
     gap: 8px;
@@ -69,8 +77,13 @@
   .spinner {
     animation: pulse 1s ease-in-out infinite;
   }
-  .error {
+  .error-bar {
     color: var(--danger);
+    font-size: 12px;
+    line-height: 1.3;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
     cursor: help;
   }
   @keyframes pulse {