Rudimentary geospatial support

[nielsenko]

Add rudimentary geospatial support. Example:

@RealmModel(ObjectType.embeddedObject)
class _Location {
  final String type = 'Point';
  List<double> coordinates = const [0, 0];
}

@RealmModel()
class _Restaurant {
  @PrimaryKey()
  late String name;
  _Location? location;
}

realm.query<Restaurant>('location geoWithin $shape');

Supported shapes are GeoBox, GeoCircle, and GeoPolygon

realm.query<Restaurant>('location geoWithin \$0', [shape]);

is also supported, thanks to realm/realm-core#6934, despite C-api not supporting geo shapes.

It works by allowing string arguments where geo shapes are required and trying to parse such from any given string, so is still implicitly dependent on inlining and hence not as efficient, but it will not force users to inline on the dart side, and hence they will automatically benefit once the C-api is updated, or we have switched to the new binding generator.

NOTE: This PR depends on a core-upgrade newer than v13.20.0, and hence a refactoring of the way errors are handled. It is currently based on top op #1398.

Fixes: #1155

[coveralls]

Pull Request Test Coverage Report for Build 6718946398

• 72 of 72 (100.0%) changed or added relevant lines in 2 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.2%) to 88.506%

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Files with Coverage Reduction	New Missed Lines	%
lib/src/list.dart	2	85.93%

Totals
Change from base Build 6718494458:	-0.2%
Covered Lines:	3419
Relevant Lines:	3863

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💛 - Coveralls

[nirinchev]

Looks reasonable - I only have nitty comments.

[nirinchev]

Does the dart generator support playing around with the accessibility of fields? If so, we could suggest a more user-friendly API, similar to what we do in .NET: https://github.com/realm/realm-dotnet/blob/641f2dc5581776b80979c69abc4c29777313bd0b/CHANGELOG.md?plain=1#L140-L162

[nielsenko]

I have added getters and setters for latitude and longitude, as well conversion methods between GeoPoint and Location in the doc comments (similar to how I did in geospatial_test.dart)

[nielsenko]

Thx @nirinchev .. just need to rerun generator 👍

[nirinchev]

Oh, yeah, needs to add the ignore lint comments that went in a bit earlier. Will do that.