Add roundtrip test for model files

[visr]

Fixes #682. It was already fixed, but this ensures it with an extra test.

[Hofer-Julian]

Looks good to me

[Hofer-Julian]

Seems like tests are still failing

[visr]

The binary diff on the database is probably too brittle. It would be more convenient to use sqldiff, which gives:

❯ sqldiff 1\database.gpkg 2\database.gpkg
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.855Z' WHERE rowid=1;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.874Z' WHERE rowid=2;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.891Z' WHERE rowid=3;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.902Z' WHERE rowid=4;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.911Z' WHERE rowid=5;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.926Z' WHERE rowid=6;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.937Z' WHERE rowid=7;
UPDATE gpkg_contents SET last_change='2024-01-30T09:47:02.947Z' WHERE rowid=8;

I cannot seem to get that tool from conda-forge though.

I wonder why Python 3.10 and 3.12 are different though, only on Windows.

[visr]

I left out the network since it really isn't a node, and is such a different beast that it usually needs to be handled separately from the nodes.

[visr]

This now compares the DataFrames rather than the GeoPackage bytes.