Support configuring log levels/sampling overrides with java app insights agent

When using the [app insights java agent](https://learn.microsoft.com/en-us/azure/azure-monitor/app/monitor-functions), the only known way to configure log levels is by using sampling overrides as described in [these docs](https://learn.microsoft.com/en-us/azure/azure-monitor/app/java-standalone-sampling-overrides). However, it's not possible to add an "applicationinsights.json" file next to the agent jar file because it's stored/shipped with the worker, not the app.

[Related IcM](https://portal.microsofticm.com/imp/v3/incidents/details/425099857/home) (internal link only)

Review the App Insights Java agent setup and the applicationinsights.json and sampling-overrides documentation first, noting that the agent JAR is shipped with the worker rather than the app. Define the supported configuration path for log levels and sampling overrides, with the work complete when those settings can be supplied in this worker-managed deployment.

Written by the indexing model from the issue text.