[ML] Explain log rate spikes: Plugin setup

[walterra]

Summary

Part of #136265.
Resolves #131607.

Sets up the boilerplate code for the aiops plugin and adds a demo page within the ML app to demonstrate single API request data streaming from Kibana server to UI client.

• General plugin code was auto-generated by the plugin generator (see Plugin tooling)
• Code that integrates the demo page within the ML plugin is in line with the data_visualizer plugin code.

Review note for kibana-operations: This touches packages/kbn-optimizer/limits.yml for the new aiops plugin to set an initial KB limit, looking at CODEOWNERS, I think that's the only file that triggered the review request.

Plugin page is available at this Kibana URL: http://localhost:5601/app/ml/aiops/explain_log_rate_spikes

The streaming demo shows a bar chart race:

Checklist

• Unit or functional tests were updated or added to match the most common scenarios
• Cross browser testing: macOS Chrome 101 / Safari 15.4 / Firefox 99 / Edge 101

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[peteharverson]

Will you set this to false before merging?

[walterra]

As discussed, we'll leave it as true for now for easier internal testing and will switch to false right before feature freeze.

[peteharverson]

Tested and overall looks good. Just left a few comments.

[pheyos]

Example stream API tests LGTM with just one observation.

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: a91b226
• Storybooks Preview
• Webpack Bundle Analyzer

Metrics [docs]

Module Count

Fewer modules leads to a faster build time

id	before	after	diff
aiops	-	77	+77
ml	1581	1584	+3
total			+80

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
aiops	-	218.1KB	⚠️ +218.1KB
ml	3.3MB	3.3MB	+2.0KB
total			+220.1KB

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
aiops	-	3.8KB	+3.8KB
ml	39.5KB	39.8KB	+312.0B
total			+4.1KB

Unknown metric groups

API count

id	before	after	diff
aiops	-	10	+10

async chunk count

id	before	after	diff
aiops	-	1	+1

ESLint disabled line counts

id	before	after	diff
aiops	-	3	+3

Total ESLint disabled count

id	before	after	diff
aiops	-	3	+3

History

• 💚 Build #43940 succeeded 6ac022a
• 💚 Build #43576 succeeded 3ee63c6
• 💛 Build #43288 was flaky 9fffb56
• 💚 Build #42988 succeeded 91e3dce
• 💚 Build #42946 succeeded d97a646
• 💚 Build #42770 succeeded cbc8b54

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @walterra

[alvarezmelissa87]

Tested and LGTM ⚡ Thanks for your work on this!! 🙌

[peteharverson]

Latest changes LGTM