fix #7417 feat(nimbus): display analysis errors on Results UI

[mikewilli]

Because

• Jetstream now makes analysis error logs available
• there is no indication in Experimenter of why results may be missing

This commit

• retrieves errors from Jetstream
• determines if errors should be displayed
  • for Experiment level errors: display errors at top of experiment if they exist
  • for Metric level errors: if the metric has errors but does not have results
• creates an error alert component to display when appropriate

Screenshots: Experiment error Metric error