Merge pull request #416 from Peefy/update-dotnet-api-docs

docs: add dotnet API reference docs

Author: Peefy

docs/reference/xlang-api/dotnet-api.md

@@ -207,15 +207,13 @@ app: AppConfig {
 
 Java Code
 
-```python
-import kcl_lib.api as api
-
-args = api.LoadPackage_Args(
-    parse_args=api.ParseProgram_Args(paths=["schema.k"]), resolve_ast=True
-)
-api = api.API()
-result = api.load_package(args)
-assert list(result.symbols.values())[0].ty.schema_name == "AppConfig"
+```java
+import com.kcl.api.*;
+
+API api = new API();
+LoadPackage_Result result = api.loadPackage(LoadPackage_Args.newBuilder().setResolveAst(true)
+    .setWithAstIndex(true)
+    .setParseArgs(ParseProgram_Args.newBuilder().addPaths("schema.k").build()).build());
 ```
 
 </p>