VTAdmin(API): Add MoveTablesCreate endpoint

[beingnoble03]

Description

This PR adds an API endpoint for creating move tables workflow.

Related Issue(s)

• VTAdmin: Enhance VReplication functionality in vtadmin UI #11690

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
• If this change is to be back-ported to previous releases, a justification is included in the PR description
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

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.
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Tests

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Backward compatibility

• Protobuf changes should be wire-compatible.
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[codecov]

Codecov Report

Attention: Patch coverage is 4.00000% with 24 lines in your changes missing coverage. Please review.

Project coverage is 68.92%. Comparing base (977b9a3) to head (33350be).
Report is 50 commits behind head on main.

Files with missing lines	Patch %	Lines
go/vt/vtadmin/http/workflows.go	0.00%	14 Missing ⚠️
go/vt/vtadmin/api.go	9.09%	10 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16690      +/-   ##
==========================================
- Coverage   68.95%   68.92%   -0.03%     
==========================================
  Files        1565     1565              
  Lines      201530   201555      +25     
==========================================
- Hits       138957   138922      -35     
- Misses      62573    62633      +60     

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[beingnoble03]

Merged changes from here into #16707. So, closing this one.