fix: UI polish and provider fixes

- Add animate-pulse CSS animation for loading states
- Add Ctrl+I/Ctrl+B markdown shortcuts in chat input
- Improve chat input resize with mirror element
- Add reasoning duration display and shimmer effect
- Add confirmation dialog for deleting all models
- Simplify RowVirtualizerDynamic resize handling
- Fix DialogType imports (type -> value)
- Fix ollama cloud model name resolution
- Make vllm auth header optional
- Various icon and styling fixes

app/assets/css/base.css

@@ -224,6 +224,45 @@ button.accent:hover {
     animation: blink 1s step-end infinite;
 }
 
+.animate-pulse {
+    background: linear-gradient(90deg,
+            currentColor 0%,
+            currentColor 35%,
+            rgba(255, 255, 255, 0.65) 50%,
+            currentColor 65%,
+            currentColor 100%);
+    background-size: 300% 100%;
+    background-repeat: no-repeat;
+    background-clip: text;
+    -webkit-background-clip: text;
+    -webkit-text-fill-color: transparent;
+    animation:
+        pulse-shimmer 2s linear infinite,
+        pulse-opacity 2s ease-in-out infinite;
+}
+
+@keyframes pulse-shimmer {
+    0% {
+        background-position: 100% 0;
+    }
+
+    100% {
+        background-position: 0% 0;
+    }
+}
+
+@keyframes pulse-opacity {
+
+    0%,
+    100% {
+        opacity: 1;
+    }
+
+    50% {
+        opacity: 0.7;
+    }
+}
+
 @keyframes blink {
 
     0%,