feat: Move flutter-build.sh

flake.nix

@@ -16,7 +16,7 @@
       installPhase = ''
         mkdir -p $out/bin
 
-        install --mode 555 src/flutter-build.sh $out/bin/flutter-build
+        install --mode 555 src/flutter/build.sh $out/bin/flutter-build
       '';
     };
     flutter-build-raw = pkgs.callPackage flutterBuildRaw {};