ISW - Input Diagnosis Improvements

[grotlue]

• Received Message count by Stream: clickable link to stream
  • We need to adjust the API system/inputs/diagnostics/${inputId} to include the stream id so we can build a link
• Message Failed metrics: clickable link to Failures stream (with input and time filter)
  • TBD @tellistone: which filters should we use?
• Content for Input Diagnosis step in input setup wizard (@tellistone, we need copy for that)
• Use correct metrics
• Add new metric org.graylog2.inputs.${inputId}.failures.input as the asterix notation in org.graylog2.inputs.codecs.*.${inputId}.failures does not work
• Add feature tests
• The current metrics are per second, should we keep them? If yes, should we make it clear to the user? @tellistone

[grotlue]

We cannot build a link for "Message Error at Input" as we don't save them yet
@AntonEbel can you check if and how we can build links to "Message Failed to process" and "Message Failed to index" (using failure_type field?)

[grotlue]

All three metrics we use are per second metrics. I checked with @tellistone and it is preferred to not use per second metrics but rather a "total in the last 15 min" metric. Can we add new metrics for that @AntonEbel?