feat(FN-998): split changes-header-actions into two-row layout

- Refactor TaskChangesTab actions header to use a two-row layout for better readability
- Add CSS for .changes-header-row-top and .changes-header-row-bottom styling
- Reorganize action buttons and filters across two rows with proper spacing
- Improve responsive behavior of the changes tab header actions

packages/dashboard/app/styles.css

@@ -3563,9 +3563,10 @@ body {
 
 .changes-header {
   display: flex;
-  align-items: center;
+  align-items: flex-start;
   justify-content: space-between;
   gap: var(--space-md);
+  flex-wrap: wrap;
 }
 
 .changes-header h4 {
@@ -3581,6 +3582,19 @@ body {
   gap: var(--space-sm);
 }
 
+.changes-header-actions-wrapper {
+  display: flex;
+  flex-direction: column;
+  align-items: flex-end;
+  gap: var(--space-xs);
+}
+
+.changes-header-actions-secondary {
+  display: inline-flex;
+  align-items: center;
+  gap: var(--space-sm);
+}
+
 .changes-nav {
   display: inline-flex;
   align-items: center;