fix(selection): clear editor highlight when selection chip is deleted

src/features/chat/controllers/selection-controller.ts

@@ -438,6 +438,7 @@ export class SelectionController {
     if (this.storedToken) {
       if (!value.includes(this.storedToken)) {
         const stale = this.storedToken;
+        this.clearHighlight();
         this.storedToken = null;
         this.storedSelection = null;
         this.tokenSink.unregister(stale);

tests/unit/features/chat/controllers/selection-controller.test.ts

@@ -157,7 +157,7 @@ describe('SelectionController', () => {
     expect(showSelectionHighlight).toHaveBeenCalledWith(editorView, 0, 4);
   });
 
-  it('drops the stored selection when the token is removed from the input', () => {
+  it('drops the stored selection and clears the highlight when the token is removed from the input', () => {
     controller.start();
     jest.advanceTimersByTime(250);
     expect(controller.hasSelection()).toBe(true);
@@ -167,6 +167,7 @@ describe('SelectionController', () => {
 
     expect(controller.hasSelection()).toBe(false);
     expect(tokenSink.unregister).toHaveBeenCalledWith(SOURCE_TOKEN);
+    expect(hideSelectionHighlight).toHaveBeenCalledWith(editorView);
   });
 
   it('collapses the editor selection on send so the chip does not come back', () => {
@@ -606,6 +607,29 @@ describe('SelectionController', () => {
       expect(mockHighlights.delete).toHaveBeenCalledWith('qoderian-selection');
     });
 
+    it('clears CSS highlight when the selection chip token is removed in reading mode', () => {
+      const anchorNode = {};
+      (global as any).document = {
+        activeElement: null,
+        getSelection: jest.fn().mockReturnValue(
+          createMockDOMSelection('reading selection', anchorNode),
+        ),
+      };
+      const mockHighlights = { set: jest.fn(), delete: jest.fn() };
+      (global as any).CSS = { highlights: mockHighlights };
+
+      controller.start();
+      jest.advanceTimersByTime(250);
+      expect(controller.hasSelection()).toBe(true);
+
+      inputEl.value = '';
+      inputEl.dispatchEvent(new Event('input', { bubbles: true }));
+
+      expect(controller.hasSelection()).toBe(false);
+      expect(tokenSink.unregister).toHaveBeenCalledWith('@notes/reading.md');
+      expect(mockHighlights.delete).toHaveBeenCalledWith('qoderian-selection');
+    });
+
     it('skips CSS highlight for disconnected DOM ranges', () => {
       const anchorNode = {};
       const mockSel = createMockDOMSelection('reading selection', anchorNode);