Go：Add build pipeline for go server and fix web login bug

build.ps1

@@ -15,11 +15,110 @@ param(
 
     [switch]$ServerOnly,  # Only build main server (Yama), skip client projects
     [switch]$Clean,       # Clean before build
-    [switch]$Publish      # Publish mode: rebuild all deps + x64 Release + UPX compress
+    [switch]$Publish,     # Publish mode: rebuild all deps + x64 Release + UPX compress
+    [switch]$GoServer     # Build Go fallback server (server/go) -> Bin/YamaGo_x64.exe
 )
 
 $ErrorActionPreference = "Stop"
 
+$rootDir = $PSScriptRoot
+$binDir = Join-Path $rootDir "Bin"
+$upxPath = Join-Path $rootDir "server\2015Remote\res\3rd\upx.exe"
+
+# Build Go fallback server. No-op (with warning) if Go compiler is not installed.
+# When -Compress is set, run UPX --best on the output (mirrors C++ publish flow).
+function Build-GoServer {
+    param(
+        [string]$Configuration,
+        [switch]$Compress
+    )
+
+    Write-Host ""
+    Write-Host "Building Go server (server/go)..." -ForegroundColor Magenta
+
+    $goCmd = Get-Command go -ErrorAction SilentlyContinue
+    if (-not $goCmd) {
+        Write-Host "WARNING: Go compiler not found in PATH. Skipping Go server build." -ForegroundColor Yellow
+        Write-Host "  Install from https://go.dev/dl/ and ensure 'go' is in PATH." -ForegroundColor DarkGray
+        return $false
+    }
+
+    Write-Host "Using Go: $($goCmd.Source)" -ForegroundColor Cyan
+
+    $goDir = Join-Path $rootDir "server\go"
+    if (-not (Test-Path $goDir)) {
+        Write-Host "ERROR: Go source directory not found at $goDir" -ForegroundColor Red
+        return $false
+    }
+
+    # Sync web assets (mirrors Makefile `sync` target — single source is server/web/index.html)
+    $webSrc = Join-Path $rootDir "server\web\index.html"
+    $webDstDir = Join-Path $goDir "web\assets"
+    if (Test-Path $webSrc) {
+        if (-not (Test-Path $webDstDir)) { New-Item -ItemType Directory -Path $webDstDir -Force | Out-Null }
+        Copy-Item -Path $webSrc -Destination (Join-Path $webDstDir "index.html") -Force
+    }
+
+    if (-not (Test-Path $binDir)) { New-Item -ItemType Directory -Path $binDir -Force | Out-Null }
+
+    $outFile = Join-Path $binDir "YamaGo_x64.exe"
+    # Release strips debug info for smaller binary; Debug keeps symbols.
+    $ldflags = if ($Configuration -eq "Debug") { "" } else { "-s -w" }
+
+    Push-Location $goDir
+    try {
+        $env:GOOS = "windows"
+        $env:GOARCH = "amd64"
+        if ($ldflags) {
+            & go build -ldflags $ldflags -o $outFile ./cmd
+        } else {
+            & go build -o $outFile ./cmd
+        }
+        $code = $LASTEXITCODE
+    } finally {
+        Pop-Location
+    }
+
+    if ($code -ne 0) {
+        Write-Host "ERROR: Go build failed (exit $code)" -ForegroundColor Red
+        return $false
+    }
+
+    $size = (Get-Item $outFile).Length / 1MB
+    Write-Host "OK: $outFile ($($size.ToString('F2')) MB)" -ForegroundColor Green
+
+    # In-place UPX compression. Failure is a warning, not an error — the
+    # uncompressed binary is still usable, and UPX occasionally refuses on
+    # certain PE sections.
+    if ($Compress) {
+        Write-Host ""
+        Write-Host "UPX compressing Go server..." -ForegroundColor Magenta
+        if (-not (Test-Path $upxPath)) {
+            Write-Host "WARNING: UPX not found at $upxPath — skipping compression" -ForegroundColor Yellow
+        } else {
+            $sizeBefore = (Get-Item $outFile).Length / 1MB
+            Write-Host "  Before: $($sizeBefore.ToString('F2')) MB" -ForegroundColor DarkGray
+            & $upxPath --best $outFile
+            if ($LASTEXITCODE -ne 0) {
+                Write-Host "WARNING: UPX compression failed, uncompressed binary kept" -ForegroundColor Yellow
+            } else {
+                $sizeAfter = (Get-Item $outFile).Length / 1MB
+                $ratio = (1 - $sizeAfter / $sizeBefore) * 100
+                Write-Host "  After:  $($sizeAfter.ToString('F2')) MB (-$($ratio.ToString('F1'))%)" -ForegroundColor Green
+            }
+        }
+    }
+    return $true
+}
+
+# Go-only fast path: skip MSBuild entirely. -Publish here means "compress the
+# Go binary too" (not the full C++ publish flow).
+if ($GoServer) {
+    $ok = Build-GoServer -Configuration $Config -Compress:$Publish
+    if (-not $ok) { exit 1 }
+    exit 0
+}
+
 # Find MSBuild (VS2019 or VS2022, including Insiders/Preview)
 # Order: Prefer installations with v142 toolset (VS2019) over VS2022 BuildTools
 $msBuildPaths = @(
@@ -72,9 +171,7 @@ elseif ($msBuild -match "\\18\\") { $vsYear = "2019 Insiders" }
 
 Write-Host "Using MSBuild: $msBuild" -ForegroundColor Cyan
 
-$rootDir = $PSScriptRoot
 $slnFile = Join-Path $rootDir "YAMA.sln"
-$upxPath = Join-Path $rootDir "server\2015Remote\res\3rd\upx.exe"
 
 # Publish mode overrides
 if ($Publish) {