fix(build): add proper line breaks for progress output

src/cli/Manifest.vala

@@ -150,9 +150,10 @@ private int install() {
     try {
         var proc = manifest.run_build(build_path, paths, SubprocessFlags.INHERIT_FDS, frac => printerr(@"Building '$(manifest.name)': $((int)(frac*100))%\r"));
         proc.wait_check();
+        printerr("\n");
     }
     catch(Error e) {
-        printerr(@"Error running build exec: $(e.message)\n");
+        printerr(@"\nError running build exec: $(e.message)\n");
         return 251;
     }