[2.x] Disable delegation on shell (#8539)

**Problem**
Currently the shell delegates request tasks even when a non-existent
task like Compile / update is requested.

**Solution**
This removes the delegation, if the input key is scoped, so it will fail.
We will, however, continue to delegate on the subproject axis,
since it's useful to use Global or ThisBuild scoping.

main/src/main/scala/sbt/internal/Act.scala

@@ -573,8 +573,14 @@ object Act {
   private def anyKeyValues(structure: BuildStructure, keys: Seq[ScopedKey[?]]): Seq[KeyValue[?]] =
     keys.flatMap(key => getValue(structure.data, key).map(KeyValue(key, _)))
 
+  /**
+   * Starting sbt 2.0.0, we will not delegate when a non-existent scoping
+   * such as Compile / update is required.
+   */
   private def getValue[T](data: Def.Settings, key: ScopedKey[T]): Option[T] =
-    if (java.lang.Boolean.getBoolean("sbt.cli.nodelegation")) data.getDirect(key)
+    if key.scope.config.isSelect ||
+      key.scope.task.isSelect
+    then data.getDirect(key)
     else data.get(key)
 
   def requireSession[T](s: State, p: => Parser[T]): Parser[T] =

sbt-app/src/sbt-test/project/no-delegate/build.sbt

@@ -0,0 +1 @@
+scalaVersion := "3.7.4"

sbt-app/src/sbt-test/project/no-delegate/test

@@ -0,0 +1,6 @@
+> compile
+> test
+
+# Fail on non-existent scoping
+-> Compile / update
+