Update drag handling: use topbar for dragging, add cursor styles, and exclude certain elements from drag initiation

web/css/linker-main.css

@@ -2029,6 +2029,7 @@
     --ml-tab-corner-size: 15px;
     --ml-tab-hover-bg: rgba(255,255,255,0.075);
     --ml-tab-separator: rgba(255,255,255,0.125);
+    cursor: default;
 }
 .ml-tab {
     display: inline-flex;

web/css/linker-shell.css

@@ -60,6 +60,12 @@
     padding: 6px 10px 0;
     border-bottom: 1px solid rgba(0, 0, 0, 0.38);
     background: #1f1f1f;
+    cursor: grab;
+    user-select: none;
+}
+
+.ml-dialog-topbar.ml-is-dragging {
+    cursor: grabbing;
 }
 
 .ml-dialog-brand,
@@ -101,6 +107,10 @@
     box-sizing: border-box;
 }
 
+.ml-dialog-topbar.ml-is-dragging #model-linker-drag-handle {
+    cursor: grabbing;
+}
+
 #model-linker-modal .ml-window-btn {
     display: flex;
     align-items: center;