Improve error handling and propagation

[minrk]

Changes:

• proxy: relay all kubernetes API errors back to the user, not just create_namespaced_job
• client: show error status and detail without traceback for HTTPStatus errors, and without HTTP request logs

As a result, invalid input like

kbatch job submit --name=List-files --command='["ls", "-lh"]' --image=alpine

goes from producing large amounts of output with no actionable info because of a generic 500 error and traceback:

[18:02:21] INFO     HTTP Request: GET https://pccompute.westeurope.cloudapp.azure.com/compute/services/kbatch/jobs/logs/add-coastline-distances-job-q6pbj/ "HTTP/1.1 500 Internal Server Error"      _client.py:1026
Traceback (most recent call last):
  File "/Users/calkoen/mambaforge/envs/jl-full/bin/kbatch", line 8, in <module>
    sys.exit(cli())
             ^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/kbatch/cli.py", line 348, in logs
    result = _core.logs(pod_name, kbatch_url, token, read_timeout=read_timeout)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/kbatch/_core.py", line 196, in logs
    result = next(gen)
             ^^^^^^^^^
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/kbatch/_core.py", line 233, in _logs
    r.raise_for_status()
  File "/Users/calkoen/mambaforge/envs/jl-full/lib/python3.11/site-packages/httpx/_models.py", line 761, in raise_for_status
    raise HTTPStatusError(message, request=request, response=self)
httpx.HTTPStatusError: Server error '500 Internal Server Error' for url 'https://pccompute.westeurope.cloudapp.azure.com/compute/services/kbatch/jobs/logs/add-coastline-distances-job-q6pbj/'
For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/500

to a short(-ish, depending on the kubernetes error), actionable error:

$ kbatch job submit --name=List-files --command='["ls", "-lh"]' --image=alpine
kbatch-proxy error 422: Job.batch "List-files-45l74" is invalid: [metadata.generateName: Invalid value: "List-files-": a lowercase RFC 1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*'), metadata.name: Invalid value: "List-files-45l74": a lowercase RFC 1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*')]

This is especially improved for 404s, where kbatch pod logs nosuchpod would produce the same big 500 traceback, but now gets the short and clear:

kbatch-proxy error 404: pods "nosuchpod" not found

I'd say this closes #52 . I don't think we need to support names k8s doesn't, and this gives users the right error to know what they need to change.