Unable to build current repository using Gradle wrapper

[fatekingsama]

Expected Behavior

The project should build successfully with the currently configured Gradle version.

Build logic should use the supported Gradle API, for example:
 application { mainClass = "..." } 

instead of the removed mainClassName property.

Actual Behaviour

mainClassName was removed in Gradle 9.
However, micronaut-grpc still attempts to set this property, which causes the build to fail on recent Gradle versions.

Steps To Reproduce

1. Clone the micronaut-grpc repository
2. Run:

./gradlew build

I can submit a PR to fix this if that would be helpful.

Environment Information

No response

Example Application

No response

Version

5.0.x