Add MoveTables list and lifecycle guidance

[no-itsbackpack]

pscale branch vtctld move-tables list lists the workflows on a branch, and MoveTables and VDiff commands now return a next_steps field telling an agent what to run next based on the workflow's actual state, so it can drive a migration to completion without guessing the order.

{
  "traffic_state": "All Reads Switched. Writes Not Switched",
  "next_steps": [
    {
      "command": "pscale branch vtctld move-tables switch-traffic mydb main --org acme --workflow commerce2customer --target-keyspace customer --tablet-types PRIMARY --format json",
      "reason": "Switch primary traffic after validating replica traffic"
    }
  ]
}

Guidance follows the Vitess lifecycle: wait while copying, VDiff once streams are running, switch replica then primary traffic, preview cleanup with complete --dry-run. Destructive complete and cancel are never suggested outright, and a VDiff mismatch returns a reason with no command so an agent stops instead of switching traffic over bad data.

next_steps is added to the existing response without altering the fields or ordering the API returns.

[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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[cursor]

Risk: medium. Left a non-blocking comment and did not approve: Cursor Bugbot completed with one unresolved high-severity finding on MoveTables list JSON handling. Human review is needed.

  

_{Sent by Cursor Approval Agent: cli-reviewer}