Reenable AGP 9 in HiltGradlePlugin.

[copybara-service]

Reenable AGP 9 in HiltGradlePlugin.

NEW: Upgraded AGP from 9.0.0-beta05 to 9.0.0.

Fixes #4944
Fixes #4979

*** Original change description ***

This required a number of changes:

• Updated Gradle 8.14.3 -> 9.2.0
• Updated shadow plugin from com.github.johnrengelman.shadow:8.1.1 to 'com.gradleup.shadow:9.2.2' (old artifact doesn't support Gradle 9).
• Updated HiltGradlePlugin to 9.0.0-beta05:
  • Migrated BaseExtension to AndroidComponentsExtension
  • Migrated BaseVariant to Component
  • Migrated variant.javaCompileOutput.classpath to variant.compileClasspath
  • Migrated variant.javaCompileOutput.destinationDirectory to variant.artifacts.use(HiltCopyTask).toGet()
  • Migrated variant.javaCompileOutput.options.bootstrapClasspath with androidExtension.sdkComponents.bootClasspath
  • Migrated variant.javaCompileOutput.options.compilerArgumentProviders with variant.javaCompilation.annotationProcessor.argumentProviders
    project.buildDir = ... to project.layout.buildDirectory.set(...)
• Updated HiltGradlePlugin tests to use AGP 9.0.0-beta05:
  • Migrate to builtin kotlin
    • removed 'kotlin-android'
    • replaced 'kotlin-kapt' with 'legacy-kapt'
    • Migrated javatests/artifacts/hilt-android/simple/app/build.gradle to kts and replace GradleVersion with custom AgpVersion. The GradleVersion does not work with APG versions like 9.0.0-beta02, so I had to do this with custom parsing.
  • removed android.kotlinOptions (removed in AGP 9)
  • removed android.useAndroidX=true (default in AGP 9)
  • added android.disallowKotlinSourceSets=false (workaround for KSP uses kotlin.sourceSets DSL when using AGP Built-In Kotlin ksp#2729)

---

RELNOTES=The next Dagger release will require AGP 9 when using the HiltGradlePlugin. This requirement is due to certain fixes only being available in AGP 9.

[Goooler]

BTW, we can edit the PR description to close #4979 and #4944.