pwd command with error handling

- Added PwdCommand class to display the current working directory. The implementation ensures error handling for unsupported flags or extra arguments, adhering to the typical behavior of the Unix pwd command.

Author: siddhant-vij

src/com/unixtools/command/filemanagement/PwdCommand.java

@@ -1,5 +1,21 @@
 package com.unixtools.command.filemanagement;
 
-public class PwdCommand {
-  
+import com.unixtools.core.Command;
+import java.nio.file.Paths;
+
+public class PwdCommand implements Command {
+  @Override
+  public void execute(String[] args) {
+    if (args.length > 0) {
+      System.out.println("Invalid usage. No flags/args are supported for pwd.");
+      return;
+    }
+
+    String currentDir = getCurrentDirectory();
+    System.out.println(currentDir);
+  }
+
+  private String getCurrentDirectory() {
+    return Paths.get("").toAbsolutePath().normalize().toString();
+  }
 }

src/com/unixtools/core/CommandFactory.java

@@ -19,6 +19,8 @@ public static Command getCommand(String commandName) {
         return new MvCommand();
       case "touch":
         return new TouchCommand();
+      case "pwd":
+        return new PwdCommand();
       default:
         return null;
     }