Implement multi-bounce occlusion approximation

Fix indentation

Allow disabling multi-bounce per material

Document multi-bounce ambient occlusion

Update FLAG_MAX in documentation

Re-order documentation

Fix documentation mismatched default

Update doc/classes/BaseMaterial3D.xml

Co-authored-by: Hugo Locurcio <hugo.locurcio@hugo.pro>

Remove multi-bounce render mode

Remove multi-bounce render mode from documentation

Remove the last mention of multi-bounce material from documentation

Default multibounce only in new projects

Update true default state of multibounce in documentation

Cleanup ifdef double negative

Update doc/classes/ProjectSettings.xml

Co-authored-by: Hugo Locurcio <hugo.locurcio@hugo.pro>

Revert "Update doc/classes/ProjectSettings.xml"

This reverts commit 021263cc152f91a19117373625b489517064b5eb.

Remove multibounce from compatibility

removed from mobile