Add Linear Referencing Functions for Spatial extension

[egutierrez-ar]

Mentioned during DuckCon#6 in Amsterdam to some DuckDB developers.

For this request, "Linear Referencing Functions" I refer to are to fulfill feature parity with PostGIS implementation of spatial functions that make use of the M dimension or fractions of the length of (Sub)Linestrings.

https://postgis.net/docs/manual-3.0/reference.html#Linear_Referencing

Particularly, we are interested in those that can be used to locate and generate geometry subsets based on the value of the M dimension of larger geometries. This is crucial for applications such as railway or roadway engineering as well as logistics.

The only function from the PostGIS manual 3.0 that we wouldn't find a use for would be ST_3DLineInterpolatePoint

For more information of usage of linear referencing see: https://en.m.wikipedia.org/wiki/Linear_referencing

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This idea has been moved from other repo on request of a maintainer
duckdb/duckdb#16204

[Maxxen]

Hi! It was nice talking to you at DuckCon!
This has been on my mind for a while, and so I've quickly implemented some of them in #497. I'll take a stab at the rest later when I find the time.

[egutierrez-ar]

Super! Great steps forward.
I like including the testing file of the functions. Some of these transformations can be really arcane, so it's nice to include them for sanity checks.
Thank you for making the time.

[egutierrez-ar]

Hi Maxxen (and other maintainers)
Just wanted to bump this discussion in case there's availability to look into what I would consider useful functions for my usecases:

• ST_InterpolatePoint
• ST_LocateAlong
• ST_LocateBetween

[PaRuBS]

Dear maintainers,

I noted that the Spatial extension supports the following functions:
ST_LineInterpolatePoint
ST_LineSubstring

but not:
https://postgis.net/docs/ST_LineLocatePoint.html

In my opinion, it would be great to add support for the latter so that one can also generate fractions of 2d line lengths. What do you think?

Thanks and kudos for all the great work!

[Maxxen]

Hello! I've added support for these functions in this PR: #645