[Logs UI] Load log stream entries using async searches

[weltenwort]

Summary

As part of the make-it-slow effort (and thereby indirectly searchable snapshots and runtime fields) we want to use Elasticsearch's async search to execute potentially expensive queries. The queries to load the log entries in the log stream and the minimap summary certainly qualify as such.

related to #86441

Acceptance criteria

• A search strategy for loading intervals of log stream entries exists.
• A search strategy for loading log stream summary data exists. (probably not needed, just use the ESE search stategy directly)
• The log stream entries are loaded using the corresponding search strategy.
• The log entries in the "view-in-context" modals are loaded using the corresponding search strategy.
• The log stream entries in the embeddable <LogStream /> component are loaded using the corresponding search strategy.
• The log stream summary is loaded using the corresponding search strategy.
• The request for log entries are cancelled when newer requests are issued.
• The request for the log summary are cancelled when newer requests are issued.
• The log entry requests can be explicitly cancelled and retried by the user.
• The previous HTTP routes are not present anymore if no other usage remains.

[elasticmachine]

Pinging @elastic/logs-metrics-ui (Team:logs-metrics-ui)

[afgomez]

Should this also affect the shared <LogStream /> component?

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Edit, I re-read the description and I see the intention is to do it as part of this issue as well.

[weltenwort]

Oops, I messed up escaping the < in <LogStream />, so it wasn't rendered correctly in the description - sorry about that 🙈

[elasticmachine]

Pinging @elastic/obs-ux-logs-team (Team:obs-ux-logs)