fix: replace hardcoded absolute path with TaskCtx.workspace, fix sandbox violations

- Replace hardcoded /home/roman/... path with TaskCtx.workspace (Mill's
  official API for the project root inside tasks)
- Remove cliBinPath (wrote outside Task.dest, hit sandbox restriction);
  buildCliBinary now writes to Task.dest/cli
- Fix testLocal sources to use moduleDir instead of os.pwd
- Add import mill.api.TaskCtx

Author: rolang

build.mill

@@ -7,6 +7,7 @@ import mill.scalanativelib.api.*
 import mill.scalalib.publish.*
 import mill.util.VcsVersionModule
 import mill.api.Task.Simple
+import mill.api.TaskCtx
 import os.Path
 
 val scalaVer = "3.8.3"
@@ -25,30 +26,10 @@ val munitVer = "1.3.0"
 
 val upickleVer = "4.4.3"
 
-def cliBinPath: os.Path = {
-  def normalise(s: String) = s.toLowerCase.replaceAll("[^a-z0-9]+", "")
-  val props = sys.props.toMap
-  val osName = normalise(props.getOrElse("os.name", "")) match {
-    case p if p.startsWith("linux")                         => "linux"
-    case p if p.startsWith("windows")                       => "windows"
-    case p if p.startsWith("osx") || p.startsWith("macosx") => "macosx"
-    case _                                                  => "unknown"
-  }
-  val arch = (
-    normalise(props.getOrElse("os.arch", "")),
-    props.getOrElse("sun.arch.data.model", "64")
-  ) match {
-    case ("amd64" | "x64" | "x8664" | "x86", bits) => s"x86_$bits"
-    case ("aarch64" | "arm64", bits)               => s"aarch$bits"
-    case _                                         => "unknown"
-  }
-  os.pwd / "target" / "bin" / s"gcp-codegen-$arch-$osName"
-}
-
-/** Build the Scala Native CLI binary and copy it to target/bin/<arch>-<os> */
+/** Build the Scala Native CLI binary */
 def buildCliBinary: T[PathRef] = Task {
   val linked = cli.nativeLink()
-  val dest = cliBinPath
+  val dest = Task.dest / "cli"
   os.makeDir.all(dest / os.up)
   os.copy.over(linked.path, dest)
   PathRef(dest)
@@ -131,7 +112,7 @@ object exampleJsoniterJson extends Module {
 // ---------------------------------------------------------------------------
 
 object testLocal extends ScalaModule {
-  override def sources = Task.Sources(os.pwd / "test-local" / "src" / "main" / "scala")
+    override def sources = Task.Sources(moduleDir / "src" / "main" / "scala")
   def scalaVersion = scalaVer
   override def moduleDeps = Seq(exampleJsoniterJson.jvm)
   override def mvnDeps = Task {
@@ -209,9 +190,9 @@ trait TestModule extends Cross.Module5[String, String, String, String, String] w
     val dest = Task.dest
     val basePkg = s"gcp.$apiName.$apiVersion.${httpSource}_${jsonCodec}_${arrayType}".toLowerCase()
     val outSrcDir = dest / "scala"
+    val ws = implicitly[TaskCtx].workspace
     val specFile =
-      // os.pwd / "modules" / "test-resources" / "src" / "main" / "resources" / s"${apiName}_${apiVersion}.json"
-      s"/home/roman/projects/rolang/google-api-codegen/modules/test-resources/src/main/resources/${apiName}_${apiVersion}.json"
+      ws / "modules" / "test-resources" / "src" / "main" / "resources" / s"${apiName}_${apiVersion}.json"
 
     val cliBin = buildCliBinary()
 
@@ -225,7 +206,7 @@ trait TestModule extends Cross.Module5[String, String, String, String, String] w
       s"-json-codec=$jsonCodec",
       s"-array-type=$arrayType",
       s"-jsoniter-json-type=_root_.example.jsoniter.Json"
-    ).call(cwd = os.pwd)
+    ).call(cwd = ws)
     Seq(PathRef(dest))
   }