Feature request: Initial Configuration vs Current Configuration support

### Brief Issue Summary

Qt Creator has this feature which is very useful:
https://doc.qt.io/qtcreator/creator-build-settings-cmake.html#initial-configuration

Initial Configuration is taken from Kit or preset, and can be adjusted further.

Start by reading the linked Qt Creator Initial Configuration documentation and then inspect how CMake Tools handles presets and configuration state. The issue names no files, tests, or entry points; done would require an agreed design for separating kit or preset values from the editable current configuration.

Written by the indexing model from the issue text.