mcp-windows-arm64 - #842

Description

Adds native Windows ARM64 coverage across MCP bundle packaging, npm/PyPI and Rust/Go/.NET launchers, the combined bundle, MCP fuzzing, OpenAI plugin smoke tests, and MCP Registry publication.

• Build windows-arm64 bundles from the signed stackql_windows_arm64.zip release asset and publish their checksum pins.
• Select the native Windows binary in the combined bundle through a PowerShell launcher that preserves argument quoting and exit codes.
• Run packaging regressions and smoke tests on windows-11-arm; retain the existing x64 emulation fuzz job.
• Render PR-only wrapper manifests from this run's bundle checksums. Publication still pins the published release assets.

Type of change

• Bug fix (non-breaking change to fix a bug).
• Feature (non-breaking change to add functionality).
• Breaking change.
• Other.

Issues referenced.

Follows #841 and the signed Windows ARM64 assets introduced in v0.12.778.

Evidence

Local checks passed:

• Actionlint 1.6.23 (workflow validation; external shellcheck/pyflakes disabled).
• Packaging regressions: 7 passed on Windows x64; 6 passed and the Windows-specific case skipped on Linux.
• Built both Windows MCP bundles from v0.12.778 ZIPs; embedded executables match their release bytes. ARM64 Authenticode signature verified as valid.
• Combined bundle schema/PE architecture checks and Windows MCP handshake, including an install path containing spaces.
• npm and PyPI Windows MCP handshake tests.
• Go SDK unit tests, vet, and Windows ARM64 cross-compilation.
• Rust fmt, unit/doc tests, and clippy with all targets/features.
• .NET 9: all 19 tests including conformance, plus dotnet format.

Checklist:

• A full round of testing has been completed, and there are no test failures as a result of these changes.
• The changes are covered with functional and/or integration robot testing.
• The changes work on all supported platforms.
• Unit tests pass locally, as per the developer guide.
• Robot tests pass locally, as per the developer guide.
• Linter passes locally, as per the developer guide.

Variations

Native Windows ARM64 execution passed in CI. The full build/robot matrix passed in CI. No query behavior changes; added packaging regressions and expanded existing MCP smoke/fuzz coverage instead of a new SQL robot scenario.

The signed macOS asset is now available on v0.12.778. CI has built all five per-platform bundles from the release assets and passed all five combined-bundle smoke tests, including native Windows ARM64. Native ARM64 packaging regressions, npm/PyPI launcher smoke tests, fuzzing, and OpenAI plugin smoke tests also passed. The complete MCP packaging workflow passed, including Rust, Go, and .NET SDK build/test/smoke jobs on native Windows ARM64. All 69 executed CI checks passed; the five publication jobs were skipped as expected for a PR.

Tech Debt

No new deferred implementation work.