reorganize repo: move shell sources into shell/, test scripts into test/

nix/package.nix

@@ -25,12 +25,12 @@ stdenvNoCC.mkDerivation {
     runHook preInstall
 
     mkdir -p $out/share/nova-shell
-    cp -r shell.qml modules assets $out/share/nova-shell/
+    cp -r shell/shell.qml shell/modules shell/assets $out/share/nova-shell/
 
     # Compile fragment shader to Qt RHI format
     qsb --qt6 \
       -o $out/share/nova-shell/modules/hex_wave.frag.qsb \
-      modules/hex_wave.frag
+      shell/modules/hex_wave.frag
 
     mkdir -p $out/bin
     makeWrapper ${lib.getExe quickshell} $out/bin/nova-shell \