Add Windows build scripts, fix multi-threaded MPQ extraction, and cross-platform temp paths

- Add build.ps1/bat, rebuild.ps1/bat, debug_texture.ps1/bat (Windows equivalents
  of existing bash scripts, using directory junctions for Data link)
- Fix asset extractor: StormLib is not thread-safe even with separate handles per
  thread. Serialize all MPQ reads behind a mutex while keeping CRC computation and
  disk writes parallel. Previously caused 99.8% extraction failures with >1 thread.
- Add SFileHasFile() check during enumeration to skip listfile-only entries
- Add diagnostic logging for extraction failures (first 5 per thread + summary)
- Use std::filesystem::temp_directory_path() instead of hardcoded /tmp/ in
  character_renderer.cpp debug dumps
- Update debug_texture.sh to use $TMPDIR fallback and glob for actual dump filenames

debug_texture.ps1

@@ -0,0 +1,64 @@
+<#
+.SYNOPSIS
+    Converts raw RGBA texture dumps to PNG for visual inspection (Windows equivalent of debug_texture.sh).
+
+.PARAMETER Width
+    Texture width in pixels. Defaults to 1024.
+
+.PARAMETER Height
+    Texture height in pixels. Defaults to 1024.
+
+.EXAMPLE
+    .\debug_texture.ps1
+    .\debug_texture.ps1 -Width 2048 -Height 2048
+#>
+
+param(
+    [int]$Width = 1024,
+    [int]$Height = 1024
+)
+
+$TempDir = $env:TEMP
+
+Write-Host "Converting debug textures (${Width}x${Height})..."
+
+# Find raw dumps — filenames include dimensions (e.g. wowee_composite_debug_1024x1024.raw)
+$rawFiles = Get-ChildItem -Path $TempDir -Filter "wowee_*_debug*.raw" -ErrorAction SilentlyContinue
+
+if (-not $rawFiles) {
+    Write-Host "No debug dumps found in $TempDir"
+    Write-Host "  (looked for $TempDir\wowee_*_debug*.raw)"
+    exit 0
+}
+
+foreach ($rawItem in $rawFiles) {
+    $raw = $rawItem.FullName
+    $png = $raw -replace '\.raw$', '.png'
+
+    # Try ImageMagick first, fall back to ffmpeg
+    if (Get-Command magick -ErrorAction SilentlyContinue) {
+        & magick -size "${Width}x${Height}" -depth 8 "rgba:$raw" "$png" 2>$null
+        if ($LASTEXITCODE -eq 0) {
+            Write-Host "Created $png (${Width}x${Height})"
+        } else {
+            Write-Host "Failed to convert $raw"
+        }
+    } elseif (Get-Command convert -ErrorAction SilentlyContinue) {
+        & convert -size "${Width}x${Height}" -depth 8 "rgba:$raw" "$png" 2>$null
+        if ($LASTEXITCODE -eq 0) {
+            Write-Host "Created $png (${Width}x${Height})"
+        } else {
+            Write-Host "Failed to convert $raw"
+        }
+    } elseif (Get-Command ffmpeg -ErrorAction SilentlyContinue) {
+        & ffmpeg -y -f rawvideo -pix_fmt rgba -s "${Width}x${Height}" -i "$raw" "$png" 2>$null
+        if ($LASTEXITCODE -eq 0) {
+            Write-Host "Created $png (${Width}x${Height})"
+        } else {
+            Write-Host "Failed to convert $raw"
+        }
+    } else {
+        Write-Host "Need 'magick' (ImageMagick) or 'ffmpeg' to convert $raw"
+        Write-Host "  Install: winget install ImageMagick.ImageMagick"
+    }
+}