[Transform] Add basic stats

[prwhelan]

Basic Stats was introduced in 8.13.0. It is faster than Transform Stats and will skip checkpointing and other supporting API calls, making it return results more reliably.

Checklist

• I have verified that the APIs in this pull request do not return sensitive data

---

Testing:

Ran changes against 8.14 snapshot:

local-diagnostics-20240404-210020 git:(main) ✗ ls commercial/transform*
commercial/transform_basic_stats.json  commercial/transform_stats.json
commercial/transform.json

➜  local-diagnostics-20240404-210020 git:(main) ✗ cat commercial/transform_basic_stats.json | jq '.'
{
  "count": 1,
  "transforms": [
    {
      "id": "last-log-from-clientip",
      "state": "stopped",
      "stats": {
        "pages_processed": 0,
        "documents_processed": 0,
        "documents_indexed": 0,
        "documents_deleted": 0,
        "trigger_count": 0,
        "index_time_in_ms": 0,
        "index_total": 0,
        "index_failures": 0,
        "search_time_in_ms": 0,
        "search_total": 0,
        "search_failures": 0,
        "processing_time_in_ms": 0,
        "processing_total": 0,
        "delete_time_in_ms": 0,
        "exponential_avg_checkpoint_duration_ms": 0,
        "exponential_avg_documents_indexed": 0,
        "exponential_avg_documents_processed": 0
      },
      "checkpointing": {
        "last": {
          "checkpoint": 0
        }
      },
      "health": {
        "status": "green"
      }
    }
  ]
}

On version 8.12:

➜  local-diagnostics-20240404-214214 git:(main) ✗ ls commercial/transform*
commercial/transform.json  commercial/transform_stats.json

[sophiec20]

@ppf2 how can we get this reviewed?

[pickypg]

I happened to be out when this PR came in and I missed it upon return.