fix: correct Docker base image to existing tag

10.0-bookworm-slim does not exist on MCR. .NET 10 SDK images use
Ubuntu Noble (24.04) as the default distro. Switch to 10.0-noble.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: LeeCampbell

autonomous/Dockerfile

@@ -2,7 +2,7 @@
 # HdrHistogram.NET Agent Container
 # .NET SDK + Claude Code + gh CLI + firewall
 # =============================================================================
-FROM mcr.microsoft.com/dotnet/sdk:10.0-bookworm-slim
+FROM mcr.microsoft.com/dotnet/sdk:10.0-noble
 RUN dotnet_version=8.0 \
     && curl -sSL https://dot.net/v1/dotnet-install.sh | bash /dev/stdin \
        --runtime dotnet --channel $dotnet_version --install-dir /usr/share/dotnet \