use pkg-config for raylib detection

build.sh

@@ -1,6 +1,19 @@
 #!/bin/bash
-set -xe
+set -euo pipefail
+
 CFLAGS="-Wall -Wextra -Wpedantic -std=c99 -O3"
 
-cc $CFLAGS -o chip8   chip8.c   -L/usr/local/lib/libraylib.a -lraylib -lm
-cc $CFLAGS -o mos6502 mos6502.c
+echo "building mos6502..."
+cc $CFLAGS -o mos6502 mos6502.c
+
+if command -v pkg-config >/dev/null; then
+    RAYLIB_FLAGS=$(pkg-config --cflags --libs raylib 2>/dev/null)
+    if [ $? -eq 0 ]; then
+        echo "building chip8..."
+        cc $CFLAGS -o chip8 chip8.c $RAYLIB_FLAGS
+    else
+        echo "raylib not found - skipping chip8..."
+    fi
+else
+    echo "pkg-config not found - skipping chip8..."
+fi