VtctldClient Reshard: add e2e tests to confirm CLI options and fix discovered issues.

[rohit-nayak-ps]

Description

Expands https://github.com/vitessio/vitess/pull/14957 to check Reshard. Found a couple of issues which are also fixed in this PR:

1. Reshard Create was not returning any response, resulting in incorrect outputs from the command.
2. The tablet types options were ignored by the Create command.

Backport to v19 since this is a bug in the vtctldclient-based commands, which were recommended in that version over the vtctlclient ones.

Related Issue(s)

https://github.com/vitessio/vitess/issues/12152 https://github.com/vitessio/vitess/pull/14957

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

[vitess-bot[bot]]

Review Checklist

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 13 lines in your changes are missing coverage. Please review.

Project coverage is 65.40%. Comparing base (696fe0e) to head (4d674b3). Report is 56 commits behind head on main.

Files	Patch %	Lines
go/vt/vtctl/workflow/server.go	0.00%	8 Missing :warning:
...tctldclient/command/vreplication/reshard/create.go	0.00%	5 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15353      +/-   ##
==========================================
- Coverage   67.41%   65.40%   -2.02%     
==========================================
  Files        1560     1561       +1     
  Lines      192752   193532     +780     
==========================================
- Hits       129952   126583    -3369     
- Misses      62800    66949    +4149     

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[mattlord]

One other note, I think that we should backport this to v18 if possible. I say that as that's when vtctldclient Reshard was added.

[rohit-nayak-ps]

Adding backport to 18.0 as suggested above, at least for the core logic fix.

Will address the nits along with the suggested addition to test coverage in follow-up tests, so as to merge this for the GA release.