[Cloud Posture] Initialize plugin on package creation and on start if installed

[kfirpeled]

Summary

In this PR we are installing needed assets (mainly indices and Transforms) only when adding the package.
Incase the plugin is already installed, initialization process takes place as well.
As it verifies prerequisite state for the cspm solution to work correctly

Checklist

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• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• If a plugin configuration key changed, check if it needs to be allowlisted in the cloud and added to the docker list
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)
• This was checked for cross-browser compatibility

Risk Matrix

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Before closing this PR, invite QA, stakeholders, and other developers to identify risks that should be tested prior to the change/feature release.

When forming the risk matrix, consider some of the following examples and how they may potentially impact the change:

Risk	Probability	Severity	Mitigation/Notes
Multiple Spaces—unexpected behavior in non-default Kibana Space.	Low	High	Integration tests will verify that all features are still supported in non-default Kibana Space and when user switches between spaces.
Multiple nodes—Elasticsearch polling might have race conditions when multiple Kibana nodes are polling for the same tasks.	High	Low	Tasks are idempotent, so executing them multiple times will not result in logical error, but will degrade performance. To test for this case we add plenty of unit tests around this logic and document manual testing procedure.
Code should gracefully handle cases when feature X or plugin Y are disabled.	Medium	High	Unit tests will verify that any feature flag or plugin combination still results in our service operational.
See more potential risk examples

For maintainers

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

[kfirpeled]

be aware, there's a use case that the package is installed without adding it to agent-policy.
That means packagePolicyPostCreate event is not being called.

so there's a case that the assets would be installed only on next server start - which is fine

[elasticmachine]

Pinging @elastic/kibana-cloud-security-posture (Team:Cloud Security Posture)

[CohenIdo]

The return value contains an unknown type. Why is that?

[kfirpeled]

fixed

[CohenIdo]

nit:
I would consider consolidating all the post create functions into one method, so maybe initialize should include onPackagePolicyPostCreateCallback as well?
wdyt?

[kfirpeled]

the callback of onPackagePolicyPostCreateCallback is not part of the initialize of the plugin.
how do you see they relate?

[kibana-ci]

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Metrics [docs]

✅ unchanged

History

• 💔 Build #40258 failed e885d4a
• 💔 Build #40222 failed b920896
• 💔 Build #40179 failed d58b417
• 💚 Build #39442 succeeded f71d9d3
• 💚 Build #39367 succeeded a736578

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@elasticmachine merge upstream