Report CLI configurations errors to RunE

[bryanhuhta]

closes #265

This change updates CLI commands to use RunE in place of Run so user configuration errors can be reported and distinguished from actual system failures. Not all commands had obvious possible user configuration errors, but I migrated all commands to use RunE in the event that in the future the command may have possible user configuration errors.

Old:

$ spicedb migrate 1 --datastore-engine
9:08PM INF set log level new level=info
9:08PM INF set tracing provider new provider=none
9:08PM FTL cannot migrate datastore engine type datastore-engine=bad
exit status 1

New:

$ spicedb migrate 1 --datastore-engine bad 
9:10PM INF set log level new level=info
9:10PM INF set tracing provider new provider=none
Error: cannot migrate datastore engine type: bad
Usage:
  spicedb migrate [revision] [flags]

Flags:
      --datastore-conn-uri string   connection string used by remote datastores (e.g. "postgres://postgres:password@localhost:5432/spicedb")
      --datastore-engine string     type of datastore to initialize ("memory", "postgres", "cockroachdb") (default "memory")
  -h, --help                        help for migrate

Global Flags:
      --log-format string                 format of logs ("auto", "human", "json") (default "auto")
      --log-level string                  verbosity of logging ("trace", "debug", "info", "warn", "error") (default "info")
      --otel-jaeger-endpoint string       jaeger collector endpoint (default "http://jaeger:14268/api/traces")
      --otel-jaeger-service-name string   jaeger service name for trace data (default "spicedb")
      --otel-provider string              opentelemetry provider for tracing ("none", "jaeger") (default "none")