Improve Monaco editor styling to better match Airflow UI

[saikiranyt2001]

The Monaco editor currently does not fully align with the Airflow UI design system.

This PR improves visual consistency by:

• Aligning font with Airflow mono font
• Adding padding for better readability
• Applying Chakra UI surface background
• Improving overall UI consistency

These changes make the editor feel more integrated with the overall UI.

Closes : #64253

[boring-cyborg]

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[saikiranyt2001]

This update improves Monaco editor styling for better UI consistency and alignment with the Airflow design system.

[shivaam]

Is it possible to add a demo of your testing?

[potiuk]

@saikiranyt2001 This PR has a few issues that need to be addressed before it can be reviewed — please see our Pull Request quality criteria.

Issues found:

• ❌ Pre-commit / static checks: Failing: CI image checks / Static checks. Run prek run --from-ref main locally to find and fix issues. See Pre-commit / static checks docs.

Note: Your branch is 102 commits behind main. Some check failures may be caused by changes in the base branch rather than by your PR. Please rebase your branch and push again to get up-to-date CI results.

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There is no rush — take your time and work at your own pace. We appreciate your contribution and are happy to wait for updates. If you have questions, feel free to ask on the Airflow Slack.

[pierrejeambrun]

This is only updating the JsonEditor but there are other places in the codebase where the monaco editor is used. Can you also update those other places?

Also can you provide screenshots of before/after change.

[Copilot]

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[pierrejeambrun]

Closing in favor of #64748 that will also handle custom themes and make a more integrated theme I believe. (and also taking care of other locations update)