Shore up Resonate errors

[dfarr]

Preserve server information when a remote store request error occurs.

resonate.errors.errors.ResonateStoreError: [300.40900] The specified promise already exists
[
  {
    "@type": "RequestError",
    "message": "Request errors are not retryable since they are caused by invalid client requests",
    "domain": "request",
    "metadata": {
      "url": "https://docs.resonatehq.io/reference/error-codes#40900"
    }
  }
]

resonate.errors.errors.ResonateStoreError: [300.40400] The specified promise was not found
[
  {
    "@type": "RequestError",
    "message": "Request errors are not retryable since they are caused by invalid client requests",
    "domain": "request",
    "metadata": {
      "url": "https://docs.resonatehq.io/reference/error-codes#40400"
    }
  }
]

Additionally:

• set the cause for a ResonateShutdownError and use new method shutdown instead of step
• retry policies now handle attempt 0 (initial attempt)

[dfarr]

We also need to recreate the web pages for our errors or remove them from the server error messages