refactor: organize into rough directories

run.sh

@@ -3,10 +3,11 @@
 BUILD_DIR=build
 
 if [ ! -d "$BUILD_DIR" ]; then
+  mkdir -p build
   cmake -B$BUILD_DIR -S. -GNinja \
     -DCMAKE_BUILD_TYPE=Debug \
     -DCMAKE_CXX_FLAGS="-Wall -Wextra" \
-    -DCMAKE_PREFIX_PATH="$HOME/Qt/6.8.2/macos" \
+    -DCMAKE_PREFIX_PATH="$HOME/Qt/6.8.6/macos" \
     -DCMAKE_COLOR_DIAGNOSTICS=ON \
     -DCMAKE_CXX_FLAGS_INIT="-DQT_QML_DEBUG"
 fi