feat(query): add api /v1/verify

[everpcpc]

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Summary

Verify endpoint to replace current select 1 / ping methods.

❯ curl -uroot: -XPOST http://localhost:8000/v1/verify | jq
{
  "tenant": "test_tenant",
  "user": "root",
  "roles": [
    "account_admin"
  ]
}

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

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This change is