[feature] Allow end point marker symbols for balloon callout style (Request in QGIS)

[qgis-bot]

Request for documentation

From pull request qgis/QGIS#58311
Author: @nyalldawson
QGIS version: 3.40

[feature] Allow end point marker symbols for balloon callout style

PR Description:

Allows rendering a marker symbol below the endpoint of the balloon callout. Designed to allow balloon callouts to reproduce the same visual appearance as the older annotation framework items.

Commits tagged with [need-docs] or [FEATURE]

"[feature] Allow end point marker symbols for balloon callout style\n\nAllows rendering a marker symbol below the endpoint of the balloon\ncallout. Designed to allow balloon callouts to reproduce the same\nvisual appearance as the older annotation framework items."