[3D] Fix reset view button

[Withalion]

Description

This PR fixes reset view button giving wrong camera positions for virtual point clouds, and also fixes a bug where resetting view multiple times would set near & far planes incorrectly. Also it fixes initial position setting of camera after opening 3D view, which should be set to top down view of whole scene.

[github-actions]

🪟 Windows builds

Download Windows builds of this PR for testing.
Debug symbols for this build are available here.
(Built from commit f4c943c)

🪟 Windows Qt6 builds

Download Windows Qt6 builds of this PR for testing.
(Built from commit f4c943c)

[github-actions]

Tests failed for Qt 6

One or more tests failed using the build from commit 8d3bb95

virtual_pointcloud_3d_overview (testPointCloud3DOverview)

virtual_pointcloud_3d_overview

Test failed at testPointCloud3DOverview at tests/src/3d/testqgspointcloud3drendering.cpp:603

• Rendered image did not match tests/testdata/control_images/3d/expected_virtual_pointcloud_3d_overview/default/expected_virtual_pointcloud_3d_overview.png (found 1344 pixels different)
• Rendered image did not match tests/testdata/control_images/3d/expected_virtual_pointcloud_3d_overview/qt6/expected_virtual_pointcloud_3d_overview.png (found 1344 pixels different)

The full test report (included comparison of rendered vs expected images) can be found here.

Further documentation on the QGIS test infrastructure can be found in the Developer's Guide.

[github-actions]

Tests failed for Qt 5

One or more tests failed using the build from commit 3455251

virtual_pointcloud_3d_overview (testPointCloud3DOverview)

virtual_pointcloud_3d_overview

Test failed at testPointCloud3DOverview at tests/src/3d/testqgspointcloud3drendering.cpp:603

• Rendered image did not match tests/testdata/control_images/3d/expected_virtual_pointcloud_3d_overview/default/expected_virtual_pointcloud_3d_overview.png (found 1510 pixels different)
• Rendered image did not match tests/testdata/control_images/3d/expected_virtual_pointcloud_3d_overview/qt6/expected_virtual_pointcloud_3d_overview.png (found 2941 pixels different)

The full test report (included comparison of rendered vs expected images) can be found here.

Further documentation on the QGIS test infrastructure can be found in the Developer's Guide.

[Withalion]

To correct myself, the feature to open the 3D scene in the same place as 2D scene is currently looking at stays. It just fixes the bug for smaller scenes where this "zoom" would move camera to point to empty space.
EDIT: fixes only reset view button not the initial position bug