feat: Standardize toolbar buttons across Orders and Products

**Issue:**
- Products: Delete button was black (bg-black), always visible
- Products: Used inline mr-2 for icon spacing
- Orders: Delete button was red (bg-red-600), conditional
- Orders: Used inline-flex gap-2 for icon spacing
- Inconsistent UX between modules

**Solution:**
1. Added "Toolbar Button Standards" to PROJECT_SOP.md
2. Updated Products to match Orders standard

**Changes to PROJECT_SOP.md:**
- Added button type definitions (Delete, Refresh, Secondary)
- Specified Delete button: bg-red-600 (NOT bg-black)
- Specified icon spacing: inline-flex items-center gap-2
- Specified conditional rendering for destructive actions
- Added 8 mandatory rules for toolbar buttons

**Changes to Products/index.tsx:**
- Delete button: bg-black → bg-red-600 text-white hover:bg-red-700
- Delete button: Always visible → Conditional (only when items selected)
- Icon spacing: inline mr-2 → inline-flex items-center gap-2
- Delete disabled: selectedIds.length === 0 → deleteMutation.isPending
- Refresh icon: inline mr-2 → inline-flex items-center gap-2

**Result:**
✅ Consistent red delete button (destructive color)
✅ Delete only shows when items selected (better UX)
✅ Consistent icon spacing (gap-2)
✅ Consistent hover effects
✅ Both modules now identical

**Visual Improvements:**
- Red delete button clearly indicates destructive action
- Cleaner toolbar when no items selected
- Better visual hierarchy

PROJECT_SOP.md

@@ -260,6 +260,59 @@ When updating an existing module to follow this pattern:
 </Toolbar>
 ```
 
+#### Toolbar Button Standards
+
+All CRUD list pages MUST use consistent button styling in the toolbar:
+
+**Button Types:**
+
+| Button Type | Classes | Use Case |
+|-------------|---------|----------|
+| **Delete (Destructive)** | `border rounded-md px-3 py-2 text-sm bg-red-600 text-white hover:bg-red-700 disabled:opacity-50 inline-flex items-center gap-2` | Bulk delete action |
+| **Refresh** | `border rounded-md px-3 py-2 text-sm hover:bg-accent disabled:opacity-50 inline-flex items-center gap-2` | Refresh data |
+| **Export/Secondary** | `border rounded-md px-3 py-2 text-sm hover:bg-accent disabled:opacity-50 inline-flex items-center gap-2` | Secondary actions |
+
+**Button Structure:**
+```tsx
+<button 
+  className="border rounded-md px-3 py-2 text-sm bg-red-600 text-white hover:bg-red-700 disabled:opacity-50 inline-flex items-center gap-2"
+  onClick={handleAction}
+  disabled={condition}
+>
+  <IconComponent className="w-4 h-4" />
+  {__('Button Label')}
+</button>
+```
+
+**Rules:**
+1. ✅ **Delete button** - Always use `bg-red-600` (NOT `bg-black`)
+2. ✅ **Icon placement** - Use `inline-flex items-center gap-2` (NOT `inline mr-2`)
+3. ✅ **Destructive actions** - Only show when items selected (conditional render)
+4. ✅ **Non-destructive actions** - Can be always visible (use `disabled` state)
+5. ✅ **Consistent spacing** - Use `gap-2` between icon and text
+6. ✅ **Hover states** - Destructive: `hover:bg-red-700`, Secondary: `hover:bg-accent`
+7. ❌ **Never use `bg-black`** for delete buttons
+8. ❌ **Never use `inline mr-2`** - use `inline-flex gap-2` instead
+
+**Toolbar Layout:**
+```tsx
+<div className="flex gap-3">
+  {/* Bulk Actions - Show only when items selected */}
+  {selectedIds.length > 0 && (
+    <button className="...bg-red-600...">
+      <Trash2 className="w-4 h-4" />
+      {__('Delete')} ({selectedIds.length})
+    </button>
+  )}
+  
+  {/* Always-visible actions */}
+  <button className="...hover:bg-accent...">
+    <RefreshCw className="w-4 h-4" />
+    {__('Refresh')}
+  </button>
+</div>
+```
+
 #### Table/List UI Standards
 
 All CRUD list pages MUST follow these consistent UI patterns: