Move controls.png to assets/ and gitignore all of build/

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -1,5 +1,4 @@
-/build/sdlamp2
-/build/sdlamp2.dSYM
+/build/
 *.mp3
 *.m4a
 positions.txt

CLAUDE.md

@@ -24,7 +24,7 @@ No test suite, no linter, no Makefile/CMake.
 
 ## Architecture
 
-Single-file C program: `src/sdlamp2.c` (~650 lines). One generated header: `src/controls_png.h` (embedded PNG byte array — regenerate with `./tools/embed_png.py build/controls.png src/controls_png.h` if the spritesheet changes).
+Single-file C program: `src/sdlamp2.c` (~650 lines). One generated header: `src/controls_png.h` (embedded PNG byte array — regenerate with `./tools/embed_png.py assets/controls.png src/controls_png.h` if the spritesheet changes).
 
 Key sections in order:
 - **Decoder struct** — holds all FFmpeg state (format/codec contexts, swr resampler, album art texture)

tools/embed_png.py

@@ -2,7 +2,7 @@
 #
 # embed_png.py — Convert a PNG file into a C header with a byte array.
 #
-# Usage: ./tools/embed_png.py build/controls.png src/controls_png.h
+# Usage: ./tools/embed_png.py assets/controls.png src/controls_png.h
 #
 
 import sys