Fine tune code suggestions setup

Tasks

• Default enable code suggestions on all namespaces reverted
  • New namespaces - !117895 (merged)
    • revert as per #408104 (closed) - !118073 (merged)
  • Existing namespaces - !117899 (merged)
    • revert as per #408104 (closed) - !118070 (merged)
• Update copy in UI - !118057 (closed)

Copy changes

Minor changes to the Code Suggestions UI to support this shift to default on. We also need to update the docs to say enabled by default. I'll open a new MR for that as I have other code suggestion changes anyway.

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