refactor: style fixes and fold combinator used instead of explicit pattern match

src/main/wacc/Main.scala

@@ -6,8 +6,7 @@ import parsley.{Failure, Success}
 import scopt.OParser
 import java.io.File
 import java.io.PrintStream
-import cats.implicits._
-import cats.effect.unsafe.implicits.global
+import cats.implicits.*
 
 import assemblyIR as asm
 import cats.effect.IO
@@ -70,28 +69,28 @@ val s = "enter an integer to echo"
 def backend(typedProg: microWacc.Program): Chain[asm.AsmLine] =
   asmGenerator.generateAsm(typedProg)
 
-
 def compile(filename: String, outFile: Option[File] = None)(using
     stdout: PrintStream = Console.out
 ): IO[Int] =
   for {
     contents <- IO(os.read(os.Path(filename)))
     result <- frontend(contents)
-    exitCode <- result match {
-      case Left(code) => IO.pure(code) // Return error code
-      case Right(typedProg) =>
+    exitCode <- result.fold(
+      IO.pure, // Return error code (handles Left case)
+      typedProg =>
         IO {
           writer.writeTo(
             backend(typedProg),
             PrintStream(outFile.getOrElse(File(filename.stripSuffix(".wacc") + ".s")))
           )
         }.as(0) // Compilation succeeded
-    }
+    )
   } yield exitCode
 
 object Main extends IOApp.Simple {
   override def run: IO[Unit] =
-  OParser.parse(cliParser, sys.env.getOrElse("WACC_ARGS", "").split(" "), CliConfig()).traverse_ { config =>
+    OParser.parse(cliParser, sys.env.getOrElse("WACC_ARGS", "").split(" "), CliConfig()).traverse_ {
+      config =>
         compile(
           config.file.getAbsolutePath,
           outFile = Some(File(".", config.file.getName.stripSuffix(".wacc") + ".s"))