Problematic use of Project.detachedConfiguration for KSP2

KSP2 uses a [detached configuration](https://github.com/google/ksp/blob/e479a7e3917e6947f6690af64c18c38d11c2292f/gradle-plugin/src/main/kotlin/com/google/devtools/ksp/gradle/KspAATask.kt#L152C1-L161C14) to resolve the `symbol-processing-aa` dependency. This is problematic because detached configurations are not visible during the build's configuration phase, so use cases like the following are made more difficult:

- Tools that aggregate a project's dependencies, such as the [GitHub Dependency Graph Gradle Plugin](https://github.com/gradle/github-dependency-graph-gradle-plugin/) and [gradle2nix](https://github.com/tadfisher/gradle2nix/tree/v2), fail to detect this configuration automatically.
- Overriding dependencies for bug triaging or local development is more difficult; the only ways I can think of is to modify the plugin source or use dependency substitution with an included build.
- The `symbol-processing-aa` dependency doesn't appear in the `dependencies` task.

For this case, I don't believe there is a technical limitation preventing the use of configurations registered at configuration time, as is done with KSP1.