The previous approach was severely broken, because the default
CRS for new projects setting was ignored as soon as a layer
was added to the project.
Instead, refine the setting to add options
- "Use CRS from first layer added": same as previous behavior,
the project CRS is set to match the first layer added to a new
project
- "Use a default CRS": CRS for a new project is set to a preset
default CRS, and is left unchanged when adding layers to the
project
Also update qgis_global_settings.ini to reflect these changes.
Fixes#27516
