Inspector Bugfixes Backport - 9..x.x

[Nightmask3]

Details:

Backport of this PR for 9.x.x.

Manual Tests:

• Ran the local ShaderGraph test project and verified all tests are passing
• Closing and opening the graph to verify serialization of layout and window sizing/positions are preserved
• Adding/removing/renaming/moving/deleting blackboard properties and keywords along with undo/redo at every stage, verified that no regressions here
• Changing property/keyword values through the inspector and watching the graph preview update and the shaders recompile, everything seems to be working as expected
• Selecting graph elements (like nodes and properties from the blackboards) and verifying that the inspector displays what is selected.
• Selecting various kinds of elements and making sure that whenever they are deselected, the inspector is hidden when nothing remains to display, including when undo/redo changes active selection.
• When color mode is set to "Precision" and the precision is changed through the graph settings in the inspector, verified that the entire graph colors update to Float/Half if the nodes are set to Inherit.