Cannot read properties of null (reading 'schema') in FormModalHeader
**Description:**
A TypeError occurs when attempting to open a form modal in the Strapi admin panel. The error indicates that the schema property is being accessed on a null value in the FormModalHeader component.

**Steps to Reproduce:**
Run the Strapi application in development mode:
npm run develop
Navigate to the admin panel.

Open a modal that utilizes FormModalHeader.

Observe the error in the browser console.

**Expected Behavior:**
The modal should open correctly, with schema properly initialized.

**Actual Behavior:**
A TypeError occurs, preventing the modal from rendering properly.

**Error Stack Trace:**
```
TypeError: Cannot read properties of null (reading 'schema')
    at FormModalHeader (http://localhost:1337/admin/node_modules/.strapi/vite/deps/chunk-ZKOR42XX.js?v=5c606d90:5227:50)
    at renderWithHooks (...)
    at updateFunctionComponent (...)
```

**Environment:**
Strapi Version: 5.11.3

Node.js Version: 18.x - 22.x

NPM Version: 6.x or later

Database: SQLite (better-sqlite3 11.3.0)

OS: Windows 10
      