revert(canvas): drop the workflow-editor panel changes from this PR

The canvas panel is under active modification elsewhere, so this PR stays
out of it. Reverts the toolbar search input, the sub-block table cell and
its overlay mirror, the messages-input textarea and its mirror, and the
block drag preview — all back to staging verbatim.

Cursor Bugbot was right about that last one and I was wrong: the preview
mirrors the drag DESTINATION (its TSDoc says "looks like a workflow block",
and 250px/16px are block-card dimensions), not the toolbar chip I had
compared it against. workflow-block-view renders the title `font-medium
text-md`, so its 500 was correct. Moot now that the file is reverted, but
worth recording so the next sweep does not repeat the mistake.

The globals `th` rule still covers the sub-block table header without a
call-site class; the explicit font-medium there simply wins over it, exactly
as staging renders today.

Author: waleedlatif1

apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/editor/components/sub-block/components/table/table.tsx

@@ -378,7 +378,7 @@ export function Table({
             <th
               key={column}
               className={cn(
-                'bg-transparent px-2.5 py-[5px] text-left text-[var(--text-tertiary)] text-sm',
+                'bg-transparent px-2.5 py-[5px] text-left font-medium text-[var(--text-tertiary)] text-sm',
                 index < columns.length - 1 && 'border-[var(--border-1)] border-r'
               )}
             >

apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/toolbar/components/drag-preview.ts

@@ -58,6 +58,7 @@ export function createDragPreview(info: DragItemInfo): HTMLElement {
   text.style.cssText = `
     color: var(--text-primary);
     font-size: 16px;
+    font-weight: 500;
     white-space: nowrap;
     overflow: hidden;
     text-overflow: ellipsis;