catch swallows network errors

[jchartrand]

This catch in the code to retrieve registry data in RegistryClient.load:

https://github.com/digitalcredentials/issuer-registry-client/blob/bb2f6d3f36bb2148a78f897850b970745886c137/src/index.ts#L115C1-L118C8

swallows all errors so that we can't then report back to the end user that there was a problem.

The error should either be propagated out, or some kind of success/fail result should be returned from the RegistryClient.load method.

To help with troubleshooting, probably best to catch the errors, and build up and return an object that records the results of every call (to retrieve registry data), rather than just throwing the exception after the first failed call. A propagated exception would prevent all subsequent calls (to the various registries) from running, and thereby reduce how much meaningful information we return. It could be, for example, that just the first registry call that fails (because its server is down), and all the others succeed. But without running all the calls we don't know that.

So, suggest we try calling all the registries (and therefore catch errors) and build up a response object like:

[
  {
    "name": "DCC Pilot Registry",
    "url": "https://digitalcredentials.github.io/issuer-registry/registry.json",
    "loaded": false
  },
  {
    "name": "DCC Sandbox Registry",
    "url": "https://digitalcredentials.github.io/sandbox-registry/registry.json",
    "loaded": true
  },
  {
    "name": "DCC Community Registry",
    "url": "https://digitalcredentials.github.io/community-registry/registry.json",
    "loaded": true
  },
  {
    "name": "DCC Registry",
    "url": "https://digitalcredentials.github.io/dcc-registry/registry.json",
    "loaded": false
  }
]