Brokers: Improve accessibility for r/o clusters

[hadisfr]

• Breaking change?

What changes did you make? (Give an overview)
There are some inconsistencies between the backend and frontend in the case of read-only clusters.
This results in enabled buttons which if you click them, get 405 error.
This PR tries to make them consistent.

• Make all configs of brokers read-only for read-only clusters
• Allow "analyze topic" for read-only clusters (Implement topic analysis stats provectus/kafka-ui#1967), which seems to do no write-level action on the real data

There may be still some inconsistencies in the ACL page.
I can not check or fix them now, because I have no running kafka cluster with authentication/ACL enabled.

Is there anything you'd like reviewers to focus on?

How Has This Been Tested? (put an "x" (case-sensitive!) next to an item)

• No need to
• Manually (please, describe, if necessary)
• Unit checks
• Integration checks
• Covered by existing automation

Checklist (put an "x" (case-sensitive!) next to all the items, otherwise the build will fail)

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (e.g. ENVIRONMENT VARIABLES)
• My changes generate no new warnings (e.g. Sonar is happy)
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged

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[Haarolean]

@hadisfr thank you for your first contribution to kafbat UI!

[hadisfr]

@hadisfr thank you for your first contribution to kafbat UI!

Thank you for your help and effort @Haarolean!