[qt/qt/qtquick3d]: Summary of bulk changes made

Git repository change summary for qt/qt/qtquick3d
Pushed by mirror-service into branch '6.12'.
Changed from 081da49086ccc80022fed018fe4f3fb3fa4014d5 to 0244eb04cf339bba4fda33c959187f484f315a78
Acknowledgement was received that this change introduces only existing code that has been pushed to another public open source repository.

This change contains the following new commits:

Git commit 0244eb04cf339bba4fda33c959187f484f315a78 by Qt Cherry-pick Bot (on behalf of Christian Strømme) on 05/08/2026 at 08:46..
Don't remove a non-child node from a layer

A layer does not set a parent reference on its direct children.
Those children (the View3D's scene root, the ImportScene dummy,
explicit cameras) are owned and kept alive by other subsystems,
e.g. the scene root by the scene manager, so leaving their parent
unset keeps the layer's lifetime decoupled from theirs, as  they
can outlive the layer.
Sharing of imported scenes is handled by the ImportScene dummy
injected in QSSGRenderLayer::setImportScene().

Added a test that removing a foreign node from a layer leaves the
list it belongs to intact.

Fixes: QTBUG-147451
Pick-to: 6.11
Change-Id: I612b97554cf625ed85e5138daa718fdb810f7263
Reviewed-by: Andy Nichols <[email protected]>
(cherry picked from commit d3ceaa2b74723e4d42fd54588e0adc27fb71c957)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
https://invent.kde.org/qt/qt/qtquick3d/-/commit/0244eb04cf339bba4fda33c959187f484f315a78