text: Title: Fix capitalisation of python (prefer Python) as per Vale suggestion
  Body: Vale recommends we use "Python" rather than "python".
  
  <img width="620" alt="image" src="https://github.com/user-attachments/assets/cc1e51ce-3dfc-44f8-b466-0e30d60bc06b">
  
  Task: Search across Vizro docs (vizro-core and vizro-ai) for instances of python (not Python) and replace with discretion. 
  
  If there are genuine cases where lower case `python` is more appropriate, use the following to switch Vale off/on in situ
  
  ```markdown
  <!-- vale off -->
  Legitimate use of lower case p ("python")
  <!--vale on-->
  ```