docs: add README screenshot section and proper .gitignore

.gitignore

@@ -2,12 +2,20 @@
 build/
 Builds/
 cmake-build-*/
+out/
+
+# CMake / generated caches
+CMakeCache.txt
+CMakeFiles/
+cmake_install.cmake
+*.cmake.user
 
 # JUCE
 JUCE/
 !JUCE/.gitkeep
+JuceLibraryCode/
 
-# IDE
+# IDE / editor
 .vscode/
 .idea/
 *.xcodeproj/
@@ -20,9 +28,14 @@ JUCE/
 *.mode2v3
 *.perspectivev3
 *.xcuserstate
+*.swp
+*~
 .DS_Store
+.AppleDouble
+.LSOverride
+._*
 
-# Compiled
+# Compiled objects / libraries
 *.o
 *.obj
 *.dylib
@@ -32,12 +45,21 @@ JUCE/
 *.dll
 *.exp
 *.pdb
+*.res
+*.asm
 
-# Plugin binaries
+# Plugin binaries / bundles
+*.vst
 *.vst3
 *.component
+*.aax
 *.app
+*.dSYM/
 
 # OS
-.DS_Store
 Thumbs.db
+Desktop.ini
+
+# Logs / misc
+*.log
+*.crash