Flyout state refactor

[PhilippeOberti]

Summary

This draft PR intends to show an alternative solution to #169661.
It mixes both the old code that was saving the state of the flyout internally in a reducer, and the new code which is purely relying on the url to save the state of the flyout.

Most situation would leverage the url, but some places (like the rule preview) would not want any data to be persisted so would benefit from having the state internally saved in the package.

There are 2 commits:

• the first one cherry picks the code from @christineweng alert preview PR and squashes them into a single one. This allows us to test the flyout changes with the rule creation page
• the second one is a squash of all the commits on the original flyout url state PR with some changes to accomodate the rule preview scenario, as well as some cleanup.

Please note the solution presented in this PR isn't finalized. It's more to entertain the discussion around potential solutions of how/where we save the state of the expandable flyout

[kibana-ci]

💔 Build Failed

• Buildkite Build
• Commit: c81ac75
• Interpreting CI Failures

Failed CI Steps

• Check Types and Build API Docs
• Jest Tests #1
• FTR Configs #3
• FTR Configs #3
• Serverless Investigations - Security Solution Cypress Tests #2
• Serverless Investigations - Security Solution Cypress Tests #2
• Investigations - Security Solution Cypress Tests #3
• Investigations - Security Solution Cypress Tests #3
• Linting

Test Failures

• [job] [logs] Jest Tests #1 / rule preview should open preview panel when clicking on button
• [job] [logs] Jest Tests #1 / should render component
• [job] [logs] Jest Tests #1 / should open preview panel when clicking on button
• [job] [logs] Serverless Investigations - Security Solution Cypress Tests #2 / Expandable flyout state sync should test flyout url sync should test flyout url sync
• [job] [logs] Investigations - Security Solution Cypress Tests #3 / Expandable flyout state sync should test flyout url sync should test flyout url sync
• [job] [logs] Serverless Investigations - Security Solution Cypress Tests #2 / Expandable flyout state sync should test flyout url sync should test flyout url sync
• [job] [logs] Investigations - Security Solution Cypress Tests #3 / Expandable flyout state sync should test flyout url sync should test flyout url sync

Metrics [docs]

Module Count

Fewer modules leads to a faster build time

id	before	after	diff
securitySolution	4706	4707	+1

Async chunks

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

id	before	after	diff
securitySolution	12.8MB	12.8MB	+2.5KB

Page load bundle

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

id	before	after	diff
securitySolution	65.3KB	65.4KB	+39.0B

History

• 💔 Build #177778 failed 16c8712
• 💔 Build #177775 failed bcd72d760e28b8265a7cca22b88d050f9472eb81

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