## Summary
Closes https://github.com/elastic/kibana/issues/191673
Closes https://github.com/elastic/kibana/issues/183566
Fixes the ability for the POST URL used to automate generation of
reports by adding a `generateExportUrl` function to the ShareMenuItemV2
interface. This function returns a dynamic export URL for PDF generation
by using the selected layout option.
Other changes: provides more strictness in type definitions by:
* splitting the types that define `ShareMenuProvider`:
* `ShareMenuProviderV2` provides the `getShareMenuItems` function
* `ShareMenuProviderLegacy` provides the `getShareMenuItemsLegacy`
function
### Release note
Fixed an issue with the export options for PNG/PDF reports in a
dashboard.
### Checklist
Delete any items that are not applicable to this PR.
- [x] Use the `generateExportUrl` function inputs to return a POST URL
that is aware of the layout mode (`print` or `preserve_layout`) and
screen dimensions
- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios
- [x] Flaky test runner:
https://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/6986
