[ENHANCEMENT] Add request jitter to prevent bursts

[abelyakin]

Description

Add a small jitter delay before time series, log, trace, and profile queries to spread requests over time. This prevents bursty query spikes when many panels load or refresh simultaneously, reducing server load.

Experienced issues in our case with live reload (5s) for huge dashboards.

Screenshots

Checklist

• Pull request has a descriptive title and context useful to a reviewer.
• Pull request title follows the [<catalog_entry>] <commit message> naming convention using one of the
  following catalog_entry values: FEATURE, ENHANCEMENT, BUGFIX, BREAKINGCHANGE, DOC,IGNORE.
• All commits have DCO signoffs.

UI Changes

• Changes that impact the UI include screenshots and/or screencasts of the relevant changes.
• Code follows the UI guidelines.
• E2E tests are stable and unlikely to be flaky.
  See e2e docs for more details. Common issues include:
  • Is the data inconsistent? You need to mock API requests.
  • Does the time change? You need to use consistent time values or mock time utilities.
  • Does it have loading states? You need to wait for loading to complete.

[jgbernalp]

@abelyakin I was checking this and although this distributes several queries short time apart each other, is probably not a solution to the root problem. I think we are missing something in the refresh to actually trigger the queries for the panels that are actually visible. IMO does not make sense to execute a query for a panel that is not visible in the browser viewport. If scroll happens then we should trigger the queries if they need a refresh, either because they are old (past the refresh interval) or they were never executed. Does that make sense?