Implement native JSON schema support

[MaggieKimani1]

### Tasks
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1733
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1763
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1793
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1765
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1789
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1790
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1791
- [x] Add host document to any model that can contain a reference.
- [x] Add a JsonSchemaReference proxy object for lazy reference resolution
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1764
- [ ] https://github.com/microsoft/OpenAPI.NET/issues/1812

[darrelmiller]

type property can be string or array in JSON Schema for 3.1

[captainsafia]

If it helps as a point of inspiration, here is the (internal) implementation of JsonSchema that might be a helpful basis for inspiration: https://github.com/dotnet/runtime/blob/c70791346cb716c02065c23d761d0743e30602ed/src/libraries/System.Text.Json/src/System/Text/Json/Schema/JsonSchema.cs