fix(list): give the content header a fixed height

min-height still let a child grow the row, and a couple of stray pixels from the selection bar pushed the grid down in table and list view. A fixed height makes overflow purely visual - nothing inside can move what follows.

css/style.css

@@ -786,10 +786,11 @@ input[type="range"]::-webkit-slider-thumb {
    table header) offsets by --hdr-h. */
 .content-header {
     display: flex; align-items: baseline; gap: 12px; margin-bottom: 20px;
-    /* Height of the batch bar — reserved even when nothing is selected, so
-       selecting something never moves the grid. .batch-bar pins itself to the
-       same value; change both together. */
-    min-height: 38px;
+    /* FIXED, not min-height: 24px of padding + 38px of bar. A minimum still
+       lets a child grow the row — a couple of stray pixels from the selection
+       bar were enough to push the whole grid down in table and list view. With
+       a fixed height nothing inside can move what follows. */
+    height: 62px;
     position: sticky; top: 0; z-index: 12;
     background: var(--bg);
     padding-top: 24px;
@@ -2681,7 +2682,7 @@ body[data-editor-position="center"]:has(#settingsPanel.is-open)::before {
     .nav-item { justify-content: center; padding: 8px; }
     .topbar { padding: 12px 16px; }
     .content { padding: 0 16px 16px; }
-    .content-header { padding-top: 16px; }
+    .content-header { padding-top: 16px; height: 54px; }   /* 16 + 38 */
     .slideover { width: 100%; }
     /* On a narrow viewport the slideover fills the screen — no point
        pushing the shell, the table isn't visible anyway. */