Update build and include sbt publish GH workflow

Sets up Anghammarad to use the sbt publish GHA workflow, removing
redundant publishing plugins for sbt and eliminating sbt config
options that are no longer required.

We also include the workflow file itself, taken from the docs.

https://github.com/guardian/gha-scala-library-release-workflow/blob/main/docs/configuration.md

.github/workflows/release-scala-client.yaml

@@ -0,0 +1,13 @@
+name: Release Scala client
+
+on:
+  workflow_dispatch:
+
+jobs:
+  release:
+    uses: guardian/gha-scala-library-release-workflow/.github/workflows/reusable-release.yml@main
+    permissions: { contents: write, pull-requests: write }
+    secrets:
+      SONATYPE_PASSWORD: ${{ secrets.AUTOMATED_MAVEN_RELEASE_SONATYPE_PASSWORD }}
+      PGP_PRIVATE_KEY: ${{ secrets.AUTOMATED_MAVEN_RELEASE_PGP_SECRET }}
+      GITHUB_APP_PRIVATE_KEY: ${{ secrets.AUTOMATED_MAVEN_RELEASE_GITHUB_APP_PRIVATE_KEY }}

build.sbt

@@ -1,3 +1,6 @@
+import sbtrelease.ReleaseStateTransformations.*
+import sbtversionpolicy.withsbtrelease.ReleaseVersion
+
 val compilerOptions = Seq(
   "-deprecation",
   "-Xfatal-warnings",
@@ -19,21 +22,12 @@ inThisBuild(Seq(
   scalacOptions ++= Seq(
     "-deprecation",
     "-Xfatal-warnings",
-    "-encoding", "UTF-8"
+    "-encoding", "UTF-8",
+    "-release:11",
   ),
   // sonatype metadata
   organization := "com.gu",
   licenses := Seq("Apache V2" -> url("https://www.apache.org/licenses/LICENSE-2.0.html")),
-  scmInfo := Some(
-    ScmInfo(
-      url("https://github.com/guardian/anghammarad"),
-      "scm:git@github.com:guardian/anghammarad"
-    )
-  ),
-  homepage := scmInfo.value.map(_.browseUrl),
-  developers := List(
-    Developer(id = "guardian", name = "Guardian", email = null, url = url("https://github.com/guardian"))
-  )
 ))
 
 val awsSdkVersion = "1.12.692"
@@ -48,20 +42,27 @@ lazy val root = project
   .in(file("."))
   .settings(
     name := "anghammarad-root",
-    // publish settings
-    releaseCrossBuild := true,
     publish / skip := true,
-    publishTo := sonatypePublishTo.value,
-    releaseProcess += releaseStepCommandAndRemaining("sonatypeRelease"),
+    // publish settings, for common and client
+    releaseCrossBuild := true,
+    releaseProcess := Seq[ReleaseStep](
+      checkSnapshotDependencies,
+      inquireVersions,
+      runClean,
+      runTest,
+      setReleaseVersion,
+      commitReleaseVersion,
+      tagRelease,
+      setNextVersion,
+      commitNextVersion,
+    ),
+    releaseVersion := ReleaseVersion.fromAggregatedAssessedCompatibilityWithLatestRelease().value,
   )
   .aggregate(anghammarad, client, common, dev)
 
 lazy val common = project
   .settings(
     name := "anghammarad-common",
-    // publish settings
-    releasePublishArtifactsAction := PgpKeys.publishSigned.value,
-    publishTo := sonatypePublishTo.value,
   )
 
 lazy val client = project
@@ -74,9 +75,6 @@ lazy val client = project
       "com.typesafe.scala-logging" %% "scala-logging" % scalaLoggingVersion,
       "org.scalatest" %% "scalatest" % scalaTestVersion % Test
     ),
-    // publish settings
-    releasePublishArtifactsAction := PgpKeys.publishSigned.value,
-    publishTo := sonatypePublishTo.value,
     assemblySettings,
   )
 
@@ -104,9 +102,9 @@ lazy val anghammarad = project
       "ch.qos.logback" % "logback-classic" % "1.5.3",
       "org.scalatest" %% "scalatest" % scalaTestVersion % Test
     ),
-    publish / skip := true,
     assembly / assemblyOutputPath := file("anghammarad/anghammarad.jar"),
     assemblySettings,
+    publish / skip := true,
   )
 
 lazy val dev = project
@@ -115,7 +113,7 @@ lazy val dev = project
     libraryDependencies ++= Seq(
       "com.github.scopt" %% "scopt" % "4.1.0"
     ),
-    publish / skip := true,
     assemblySettings,
+    publish / skip := true,
   )
   .dependsOn(common, anghammarad, client)

project/plugins.sbt

@@ -2,12 +2,9 @@ addSbtPlugin("com.github.sbt" % "sbt-native-packager" % "1.9.16")
 
 addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "2.2.0")
 
-addSbtPlugin("com.gu" % "sbt-riffraff-artifact" % "1.1.18")
+addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.12.0")
 
+// for publishing the scala client
 addSbtPlugin("com.github.sbt" % "sbt-release" % "1.4.0")
-
-addSbtPlugin("com.github.sbt" % "sbt-pgp" % "2.2.1")
-
 addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "3.10.0")
-
-addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.12.0")
+addSbtPlugin("ch.epfl.scala" % "sbt-version-policy" % "3.2.0")