Fix GridTable: replace ternary chain with IIFE for cell rendering

Chained ternary (colored ? div : multiline ? textarea : input) caused
webpack SWC parser issues. Replaced with IIFE {(() => { if/return })()}
which is more robust and readable.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

admin-lehrer/components/grid-editor/GridTable.tsx

@@ -504,7 +504,11 @@ export function GridTable({
                         />
                       )}
                       {/* Per-word colored display when not editing */}
-                      {hasColoredWords && !isSelected ? (
+                      {(() => {
+                        const cellText = cell?.text ?? ''
+                        const isMultiLine = cellText.includes('\n')
+                        if (hasColoredWords && !isSelected) {
+                          return (
                             <div
                               className={`w-full px-2 cursor-text truncate ${isBold ? 'font-bold' : 'font-normal'}`}
                               onClick={(e) => {
@@ -530,10 +534,13 @@ export function GridTable({
                                 </span>
                               ))}
                             </div>
-                      ) : (cell?.text ?? '').includes('\n') ? (
+                          )
+                        }
+                        if (isMultiLine) {
+                          return (
                             <textarea
                               id={`cell-${cellId}`}
-                            value={cell?.text ?? ''}
+                              value={cellText}
                               onChange={(e) => onCellTextChange(cellId, e.target.value)}
                               onFocus={() => onSelectCell(cellId)}
                               onClick={(e) => {
@@ -548,18 +555,20 @@ export function GridTable({
                                   onNavigate(cellId, e.shiftKey ? 'left' : 'right')
                                 }
                               }}
-                            rows={(cell?.text ?? '').split('\n').length}
+                              rows={cellText.split('\n').length}
                               className={`w-full px-2 bg-transparent border-0 outline-none resize-none ${
                                 isBold ? 'font-bold' : 'font-normal'
                               }`}
                               style={{ color: cellColor || undefined }}
                               spellCheck={false}
                             />
-                        ) : (
+                          )
+                        }
+                        return (
                           <input
                             id={`cell-${cellId}`}
                             type="text"
-                            value={cell?.text ?? ''}
+                            value={cellText}
                             onChange={(e) => onCellTextChange(cellId, e.target.value)}
                             onFocus={() => onSelectCell(cellId)}
                             onClick={(e) => {
@@ -576,7 +585,7 @@ export function GridTable({
                             spellCheck={false}
                           />
                         )
-                      )}
+                      })()}
                     </div>
                   )
                 })