`app run` should resolve native assembly dependencies

[nblumhardt]

Some NuGet packages include platform-specific runtime/native dependencies (for example, Microsoft.Data.SqlClient). When these packages are bundled into Seq Apps, the seqcli-based app host does not currently attempt to load the native dependencies, and the packaged app doesn't function.

It's possible to work around this manually to target a single native platform, for example by overwriting the default Microsoft.Data.SqlClient.dll assembly with a platform-specific one, and pulling Microsoft.Data.SqlClient.SNI.dll up from the nested runtime/native dependency folder to the root of the package, but this is tricky to get right, and only supports one platform at a time.

seqcli app run should use the framework's reference resolution logic to automatically pick up and load the correct native dependencies from the default package layout.