akka-actor-typed 是为 Scala 2.12、2.13 而不是 Scala 3 发布的

akka-actor-typed is published for Scala 2.12, 2.13, not for Scala 3

https://mvnrepository.com/artifact/com.typesafe.akka/akka 演员类型

试试兼容模式

lazy val foo = project.in(file("foo"))
  .settings(
    scalaVersion := "3.0.0",
    libraryDependencies += 
      ("com.typesafe.akka" %% "akka-actor-typed" % "2.6.15")
        .cross(CrossVersion.for3Use2_13)
  )

https://docs.scala-lang.org/scala3/guides/migration/compatibility-classpath.html