feat(build): add build scripts for Linux and Windows with commit hash and build time

build-win-x86_64.bat

@@ -0,0 +1,33 @@
+@echo off
+setlocal enabledelayedexpansion
+
+echo Building for Windows (amd64)...
+
+:: Get git commit hash (shortened to 7 characters, can also use full)
+for /f %%i in ('git rev-parse --short HEAD') do set COMMIT=%%i
+
+:: Get UTC time
+for /f %%i in ('powershell -Command "Get-Date -Format 'yyyy-MM-ddTHH:mm:ssZ'"') do set BUILD_DATE=%%i
+
+:: Set environment variables for Windows build
+set GOOS=windows
+set GOARCH=amd64
+set CGO_ENABLED=0
+
+:: Build -ldflags
+set LDFLAGS=-X main.BuildTime=%BUILD_DATE% -X main.CommitHash=%COMMIT%
+
+:: Set output file name
+set OUTPUT=nukumizu-windows-amd64.exe
+
+echo Commit: %COMMIT%
+echo BuildDate: %BUILD_DATE%
+echo Output: %OUTPUT%
+
+go build -ldflags "%LDFLAGS%" -o "%OUTPUT%" .
+
+if %errorlevel% equ 0 (
+    echo Build succeeded: %OUTPUT%
+) else (
+    echo Build failed.
+)