bug fix for preview version with extra '.'

Author: nagilson

src/Installer/Microsoft.Dotnet.Installation/Internal/ChannelVersionResolver.cs

@@ -107,8 +107,12 @@ public static bool IsValidChannelFormat(string channel)
             return true;
         }
 
+        // Strip prerelease suffix (e.g., "10.0.100-preview.1.32640" -> "10.0.100")
+        var dashIndex = channel.IndexOf('-');
+        var versionPart = dashIndex >= 0 ? channel.Substring(0, dashIndex) : channel;
+
         // Try to parse as a version-like string
-        var parts = channel.Split('.');
+        var parts = versionPart.Split('.');
         if (parts.Length == 0 || parts.Length > 4)
         {
             return false;

src/Installer/dotnetup/Telemetry/ErrorCodeMapper.cs

@@ -251,7 +251,7 @@ private static ExceptionErrorInfo MapIOException(IOException ioEx, string? stack
 
             var inner = ex.InnerException;
             // Limit depth to prevent infinite loops and overly long strings
-            const int maxDepth = 5;
+            const int maxDepth = 10;
             var depth = 0;
             while (inner != null && depth < maxDepth)
             {