chore: fix build scripts to create build directory and update gitignore

- Update all build scripts (.sh and .bat) to automatically create build directory if it doesn't exist
- Fix 'can't cd to build' error that occurred when build directory was missing
- Update .gitignore to exclude build artifacts and IDE files
- Add proper navigation to project root in build_dev.bat for consistency

.gitignore

@@ -1 +1,2 @@
 .vscode
+build/

scripts/build_dev.bat

@@ -7,7 +7,11 @@ echo ReiLua - Development Build
 echo ================================
 echo.
 
-REM Navigate to build directory
+REM Get script directory and navigate to project root
+cd /d "%~dp0.."
+
+REM Create and navigate to build directory
+if not exist "build" mkdir build
 cd build
 if errorlevel 1 (
     echo ERROR: Cannot access build directory

scripts/build_dev.sh

@@ -7,7 +7,12 @@ echo "ReiLua - Development Build"
 echo "================================"
 echo ""
 
-# Navigate to build directory
+# Get the script directory and navigate to project root
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+cd "$SCRIPT_DIR/.." || exit 1
+
+# Create and navigate to build directory
+mkdir -p build
 cd build || exit 1
 
 # Clean old embedded files (important for dev builds!)

scripts/build_release.bat

@@ -7,13 +7,17 @@ echo ReiLua - Release Build
 echo ================================
 echo.
 
+REM Get script directory and navigate to project root
+cd /d "%~dp0.."
+
 REM Check if we're in the right directory
 if not exist "CMakeLists.txt" (
-    echo ERROR: Please run this script from the ReiLua root directory
+    echo ERROR: Cannot find CMakeLists.txt in project root
     exit /b 1
 )
 
-REM Navigate to build directory
+REM Create and navigate to build directory
+if not exist "build" mkdir build
 cd build
 if errorlevel 1 (
     echo ERROR: Cannot access build directory

scripts/build_release.sh

@@ -7,13 +7,18 @@ echo "ReiLua - Release Build"
 echo "================================"
 echo ""
 
+# Get the script directory and navigate to project root
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+cd "$SCRIPT_DIR/.." || exit 1
+
 # Check if we're in the right directory
 if [ ! -f "CMakeLists.txt" ]; then
-    echo "ERROR: Please run this script from the ReiLua root directory"
+    echo "ERROR: Cannot find CMakeLists.txt in project root"
     exit 1
 fi
 
-# Navigate to build directory
+# Create and navigate to build directory
+mkdir -p build
 cd build || exit 1
 
 # Clean old embedded files