GHCR image recovery
- Docker build stage now builds natively for BUILDPLATFORM instead of the target platform, fixing a QEMU crash that blocked 0.2.5's GHCR publish
- 0.2.5 shipped to npm, MCP Registry, and GitHub Releases but never got a container image — 0.2.6 is the first tagged image, carrying that release's mcp-ts-core 0.12.3 upgrade and other changes