fix(cli): fix cursor left-move stalling at hard-wrapped line boundary

packages/cli/src/ui/components/shared/text-buffer.test.ts

@@ -1123,6 +1123,26 @@ describe('useTextBuffer', () => {
       expect(state.viewportVisualLines).toEqual(['l1', 'l2', 'l3']);
       expect(state.visualCursor).toEqual([0, 0]);
     });
+
+    it('moves left across a hard-wrapped single-line boundary', () => {
+      const { result } = renderHook(() =>
+        useTextBuffer({
+          initialText: '1234567890ABCDE',
+          initialCursorOffset: 10,
+          viewport: { width: 10, height: 1 },
+          isValidPath: () => false,
+        }),
+      );
+
+      expect(getBufferState(result).viewportVisualLines).toEqual(['ABCDE']);
+
+      act(() => result.current.move('left'));
+
+      const state = getBufferState(result);
+      expect(state.cursor).toEqual([0, 9]);
+      expect(state.visualCursor).toEqual([0, 9]);
+      expect(state.viewportVisualLines).toEqual(['1234567890']);
+    });
   });
 
   describe('Undo/Redo', () => {

packages/cli/src/ui/components/shared/text-buffer.ts

@@ -1397,9 +1397,29 @@ function textBufferReducerLogic(
             } else if (newVisualRow > 0) {
               newVisualRow--;
               newVisualCol = cpLen(visualLines[newVisualRow] ?? '');
+              const previousMapping = visualToLogicalMap[newVisualRow];
+              if (previousMapping) {
+                const [previousLogRow, previousLogStartCol] = previousMapping;
+                const previousCursorCol = previousLogStartCol + newVisualCol;
+                if (
+                  previousLogRow === cursorRow &&
+                  previousCursorCol === cursorCol &&
+                  newVisualCol > 0
+                ) {
+                  newVisualCol--;
+                }
+              }
             }
             break;
           case 'right':
+            // No stall-fix needed here (unlike 'left' above): the cursor
+            // resolver (calculateVisualCursorFromLayout) selects segments with
+            // a strict `logicalCol < nextStartColInLogical`, so a cursor at a
+            // hard-wrap boundary always lands at the START of the next visual
+            // row, not the end of the current one — wrapping right never maps
+            // back to the same logical position. If that segment selection ever
+            // changes (e.g. `<` → `<=`), a symmetric decrement would be needed
+            // here to avoid a mirror-image right-movement stall.
             newPreferredCol = null;
             if (newVisualCol < currentVisLineLen) {
               newVisualCol++;