Fix Windows release upload: URL-encode filenames with spaces

Use [System.Uri]::EscapeDataString for proper encoding of filenames
containing spaces in the Gitea API URL. Add size logging and error handling.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitea/workflows/build-windows.yml

@@ -140,7 +140,9 @@ jobs:
           # Upload artifacts
           Get-ChildItem -Path artifacts -Recurse -Include *.msi,*.exe | ForEach-Object {
             $filename = $_.Name
-            Write-Host "Uploading ${filename}..."
+            $encodedName = [System.Uri]::EscapeDataString($filename)
+            $size = [math]::Round($_.Length / 1MB, 1)
+            Write-Host "Uploading ${filename} (${size} MB)..."
 
             # Delete existing asset with same name
             try {
@@ -152,7 +154,12 @@ jobs:
             } catch {}
 
             # Upload
-            Invoke-RestMethod -Uri "${REPO_API}/releases/${RELEASE_ID}/assets?name=${filename}" `
+            try {
+              Invoke-RestMethod -Uri "${REPO_API}/releases/${RELEASE_ID}/assets?name=${encodedName}" `
                 -Method Post -Headers $Headers -ContentType "application/octet-stream" `
                 -InFile $_.FullName
+              Write-Host "Upload successful: ${filename}"
+            } catch {
+              Write-Host "WARNING: Upload failed for ${filename}: $_"
+            }
           }