Fix T94144: Duplicate edges in dual mesh node

The duplicated edges were caused by 'oversubdivided' edges, i.e. edges
where some of the vertices on them are only connected to two polygons.
The fix finds these vertices and 'dissolves' them so that only one edge
is created.

For most 'normal' meshes this shouldn't occurr, or only very little, so
the performance impact of this change should be neglegible. In practice
this is also avoidable by triangulating the mesh first.

Differential Revision: https://developer.blender.org/D13445

Geometry Nodes: Dual Mesh Node

This node calculates the dual of the input mesh. This means that faces
get replaced with vertices and vertices with faces. In principle this
only makes sense when the mesh in manifold, but there is an option to
keep the (non-manifold) boundaries of the mesh intact.

Attributes are propagated:
- Point domain goes to face domain and vice versa
- Edge domain and Face corner domain gets mapped to itself
Because of the duality, when the mesh is manifold, the attributes get
mapped to themselves when applying the node twice.

Thanks to Leul Mulugeta (@Leul) for help with the
ascii diagrams in the code comments.

Note that this does not work well with some non-manifold geometry,
like an edge connected to more than 2 faces, or a vertex connected to
only two faces, while not being in the boundary. This is because there
is no good way to define the dual at some of those points. This type
of non-manifold vertices are just removed for this reason.

Differential Revision: https://developer.blender.org/D12949

Geometry Nodes: Dual Mesh Node

This node calculates the dual of the input mesh. This means that faces
get replaced with vertices and vertices with faces. In principle this
only makes sense when the mesh in manifold, but there is an option to
keep the (non-manifold) boundaries of the mesh intact.

Attributes are propagated:
- Point domain goes to face domain and vice versa
- Edge domain and Face corner domain gets mapped to itself
Because of the duality, when the mesh is manifold, the attributes get
mapped to themselves when applying the node twice.

Thanks to Leul Mulugeta (@Leul) for help with the
ascii diagrams in the code comments.

Note that this does not work well with some non-manifold geometry,
like an edge connected to more than 2 faces, or a vertex connected to
only two faces, while not being in the boundary. This is because there
is no good way to define the dual at some of those points. This type
of non-manifold vertices are just removed for this reason.

Differential Revision: https://developer.blender.org/D12949

Fix T92149: Crash in delete geometry node after curve fill node

There was only a check for the component but not for if it was empty.
Because the curve fill node produces an empty curve component, a
nullptr was read, causing a crash. Generally nodes shouldn't produce
empty components, but currently we cannot rely on that fact.

Differential Revision: https://developer.blender.org/D12838

Fix T92150: Incorrect invert in Delete Geometry node

The selection was inverted when deleting points from a spline.

Differential Revision: https://developer.blender.org/D12840

Geometry Nodes: Separate and Delete Geometry for fields

Delete Geometry:
This adds a copy of the old node in the legacy folder and updates the
node to work with fields. The invert option is removed, because it is
something that should be very easy with fields, and to be consistent
with other nodes which have a selection. There is also a dropdown to
select the domain, because the domain can't be determined from the
field input. When the domain does not belong on any of the components
an info message is displayed.

Separate Geometry:
A more general version of the old Point Separate node. The "inverted"
output is the same as using the delete geometry node.

Differential Revision: https://developer.blender.org/D12574

Geometry Nodes: Separate + Delete Geometry for fields

Delete Geometry:
This adds a copy of the old node in the legacy folder and updates the node to
work with fields. The invert option is removed, because it something that should
be very easy with fields, and to be consistent with other nodes which have a
selection. There is also a dropdown to select the domain, because the domain
can't be determined from the field input. When the domain does not belong on
any of the components an info message is displayed.

{F10416062}

Separate Geometry:
A more general version of the old Point Separate node. The "inverted" output is the
same as using the delete geometry node.

{F10518721}

Possible things to change:
- The name of the outputs of the Separate Geometry node
- Add option for "smooth" {D10979} . This is probably best for a dedicated node since it only applies to meshes.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12574

Geometry Nodes: Separate + Delete Geometry for fields

Delete Geometry:
This adds a copy of the old node in the legacy folder and updates the node to
work with fields. The invert option is removed, because it something that should
be very easy with fields, and to be consistent with other nodes which have a
selection. There is also a dropdown to select the domain, because the domain
can't be determined from the field input. When the domain does not belong on
any of the components an info message is displayed.

{F10416062}

Separate Geometry:
A more general version of the old Point Separate node. The "inverted" output is the
same as using the delete geometry node.

{F10518721}

Possible things to change:
- The name of the outputs of the Separate Geometry node
- Add option for "smooth" {D10979} . This is probably best for a dedicated node since it only applies to meshes.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12574

Geometry Nodes: Add labels for switch node texture sockets

This makes texture sockets have a label by default. This can be changed
by adding the SOCK_HIDE_LABEL flag to the socket. With this change the
switch node now shows the labels "True" and "False" like for the other
types of sockets.

Fix T89415: update multi input indices after deleting a node

When deleting a node, links attached to that node are deleted, but if one
of those links was connected to a multi input socket, the indices of the
other links connected to it were not updated. This adds updates both in
the case of a normal delete as well as after a delete with reconnect.

Differential Revision: https://developer.blender.org/D11716