a new function to create 1d2d links on boundary nodes

[xldeltares]

Is your feature request related to a problem? Please describe.
This feature is related to create correct 1D2D modells for an urba system, i.e. pipes. Currently the 1d_to_2d function will not setup 1d2d links at the boundaries. This is desired for river systems where boundaries have boundary conditions. However, We use hydromt-delft3dfm for setting up both river and pipe systems. In a pipe system, most of the time, a "boundary node" is no different than other nodes, which can interact with 2D layer via 1D2D links. There are indeed exceptions where a downstream boundary node (an outlet) has a boundary condition representing a water level, but we should allow the user to decide whether they want 1D2D links at these exception locations. See a case below.

Describe the solution you'd like
The ability to create 1D2D links including all boundaries. or the ability to create 1D2D links for a subset of nodes.

Describe alternatives you've considered
We tested all available functions in hydrolib-core for creating 1d2dlinks, which all failed to deliver the results desired.

_link_from_1d_to_2d:
self.meshkernel.contacts_compute_single(node_mask=node_mask, polygons=polygon)
self._process()
_link_from_2d_to_1d_embedded:
self.meshkernel.contacts_compute_with_points(node_mask=node_mask, points=points)
self._process()
_link_from_2d_to_1d_lateral:
self.meshkernel.contacts_compute_boundary(
            node_mask=node_mask, polygons=polygon, search_radius=search_radius
        )
self._process()

Additional context
Whether this function also needs to be in hydrolib or hydrolib-core. Related issue can be found here: Deltares/HYDROLIB#128

[xldeltares]

Following up this issue with the help from @lucacarniato:

After checking, it is confirmed that the function contacts_compute_single no longer limits the 1D2D links being generated from boundary nodes.

But in the following tests, when creating 1d2d links using the function contacts_compute_single, no 1D2D links are created at the boundary. The node mask suggests that all nodes are used.

Screenshot of the function:

values of node mask:

Resulting mesh: note how the boundaries don't have green links.

@lucacarniato , could you please help again? I am using meshkernel 1.0.0 release and I tried to switch to git main, but did not change the results. Thanks!