Bump agp from 8.13.0 to 9.1.0

Bumps `agp` from 8.13.0 to 9.1.0.

Updates `com.android.library` from 8.13.0 to 9.1.0

Updates `com.android.kotlin.multiplatform.library` from 8.13.0 to 9.1.0

---
updated-dependencies:
- dependency-name: com.android.library
  dependency-version: 9.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: com.android.kotlin.multiplatform.library
  dependency-version: 9.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -1,6 +1,6 @@
 [versions]
 skainet = "0.16.0"
-agp = "8.13.0"
+agp = "9.1.0"
 jacksonDatabind = "2.21.1"
 jsonSchemaValidator = "3.0.0"
 jsonSchemaValidatorVersion = "0.5.4"