fix: plusieurs retours UX/UI (#58)

| Numéro du ticket | Titre du ticket |
|------------------|-----------------|
|                  |                 |

## Description de la PR

## Modification du .env

## Check list

- [ ] Pas de régression
- [ ] TU/TI/TF rédigée
- [ ] TU/TI/TF OK
- [ ] CHANGELOG modifié

---------

Co-authored-by: THOLOT DECHENE Matthieu <matthieu@yuno.malio.fr>
Co-authored-by: matthieu <matthieu@yuno.malio.fr>
Reviewed-on: #58
Co-authored-by: tristan <tristan@yuno.malio.fr>
Co-committed-by: tristan <tristan@yuno.malio.fr>

app/components/malio/input/InputTextArea.test.ts

@@ -149,4 +149,38 @@ describe('MalioInputTextArea', () => {
     expect(wrapper.find('p.text-m-success').exists()).toBe(false)
     expect(wrapper.get('p.text-m-danger').text()).toBe('Textarea error')
   })
+
+  it('renders as a single root element (works as a single grid item)', () => {
+    const host = document.createElement('div')
+    document.body.appendChild(host)
+    const wrapper = mount(InputTextAreaForTest, {
+      attachTo: host,
+    })
+
+    // host > div[data-v-app] > component roots
+    const app = host.firstElementChild as HTMLElement
+    expect(app.children.length).toBe(1)
+
+    wrapper.unmount()
+    host.remove()
+  })
+
+  it('applies primary scrollbar class on focus', async () => {
+    const wrapper = mount(InputTextAreaForTest)
+
+    expect(wrapper.get('textarea').classes()).not.toContain('textarea-scrollbar-primary')
+
+    await wrapper.get('textarea').trigger('focus')
+
+    expect(wrapper.get('textarea').classes()).toContain('textarea-scrollbar-primary')
+  })
+
+  it('removes primary scrollbar class on blur', async () => {
+    const wrapper = mount(InputTextAreaForTest)
+
+    await wrapper.get('textarea').trigger('focus')
+    await wrapper.get('textarea').trigger('blur')
+
+    expect(wrapper.get('textarea').classes()).not.toContain('textarea-scrollbar-primary')
+  })
 })