VTOrc cleanup: Remove unused CLI code and move relevant APIs to the new VTOrc UI

[GuptaManan100]

Description

This PR removes the unused CLI code from VTOrc and also removes the APIs register on the VTOrc's old UI that it inherited from the orchestrator.

Instead, a bunch of APIs have been moved to the servenv architecture that is now available with VTOrc. We can even port more APIs from the old UI as we see fit.

This PR moved the following APIs -

• /api/problems - moved with the same name and prints the instances that have problems. Also, the API has been extended to support filtering using the keyspace and shard name.
• /api/disable-global-recoveries - moved while remaining functionally the same
• /api/enable-global-recoveries - moved while remaining functionally the same
• /api/health - Moved to /debug/health in accordance with the other binaries in Vitess
• /api/replication-analysis - Moved while remaining functionally the same. The output format is slightly different now. It is json format and parseable on the user end.
• /api/lb-check or /api/_ping - These have not been moved, since we already get debug/liveness out of the box with servenv.

Related Issue(s)

• RFC: Orchestrator as a native Vitess component #6612

Checklist

• "Backport me!" label has been added if this change should be backported
• Tests were added or are not required
• Documentation was added or is not required. Website docs are required but will be added after RC-1 of v15 and the documentation for the release notes will be added as part of VTOrc Cleanup - Configs, APIs and old UI #11356 which will also remove configs related to the APIs

Deployment Notes

[vitess-bot]

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

• Ensure that the Pull Request has a descriptive title.
• If this is a change that users need to know about, please apply the release notes (needs details) label so that merging is blocked unless the summary release notes document is included.
• If a new flag is being introduced, review whether it is really needed. The flag names should be clear and intuitive (as far as possible), and the flag's help should be descriptive. Additionally, flag names should use dashes (-) as word separators rather than underscores (_).
• If a workflow is added or modified, each items in Jobs should be named in order to mark it as required. If the workflow should be required, the GitHub Admin should be notified.

Bug fixes

• There should be at least one unit or end-to-end test.
• The Pull Request description should either include a link to an issue that describes the bug OR an actual description of the bug and how to reproduce, along with a description of the fix.

Non-trivial changes

• There should be some code comments as to why things are implemented the way they are.

New/Existing features

• Should be documented, either by modifying the existing documentation or creating new documentation.
• New features should have a link to a feature request issue or an RFC that documents the use cases, corner cases and test cases.

Backward compatibility

• Protobuf changes should be wire-compatible.
• Changes to _vt tables and RPCs need to be backward compatible.
• vtctl command output order should be stable and awk-able.