[WSLC] Consume WSLC SDK from MxcDependencies feed (2.9.3)

[Soham Das (SohamDas2021)]

📖 Description

Migrates the WSLc SDK (Microsoft.WSL.Containers) from a local .nupkg to consuming it from the anonymous read MxcDependencies Azure Artifacts feed and bumps the pinned version from 2.8.1 to 2.9.3. nuget.org is not allowlisted in the 1ES build pool, so the feed is used directly via a stable content URL.

Swapped local 2.8.1.nupkg -> 2.9.3.nupkg; external/wslc-sdk/README.md rewritten for the feed-first + fallback flow.

🔗 References

🔍 Validation

✅ Checklist

• Signed the Contributor License Agreement
• Linked to an issue
• Updated documentation (if applicable)
• Updated Copilot instructions (if build, architecture, or conventions changed)
• If this PR changes Cargo.lock, the dependency-feed-check check passes (see docs/pull-requests.md)

📋 Issue Type

• Bug fix
• Feature
• Task

---

GitHub Actions runs the PR validation build automatically. The ADO pipeline
(MXC-PR-Build) is the Azure version of the PR pipeline, kept in parity with the GitHub
Actions build; it runs on merge to main, and Microsoft reviewers with write access can trigger it
on a PR with /azp run. See docs/pull-requests.md.

If the dependency-feed-check check fails on a new dependency, the crate must be added to
the feed before the PR can pass. See docs/pull-requests.md
for the steps.

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.

[Copilot]

Pull request overview

This PR updates MXC’s WSLC backend to consume the Microsoft.WSL.Containers SDK from the public, anonymous-read MxcDependencies Azure Artifacts feed (instead of relying solely on a locally vendored .nupkg), and bumps the pinned SDK/runtime version to 2.9.3. It also updates Rust/TypeScript/docs references to remove hard-coded “2.8.1 vendored runtime” wording and aligns bindings/call sites with the newer SDK surface.

Changes:

• Update wslc_common build script to download/extract the WSLC SDK .nupkg from the MxcDependencies feed (with WSLC_SDK_PATH override and vendored fallback).
• Update WSLC FFI bindings + runner to reflect SDK ABI/symbol changes (e.g., WslcGetMissingComponents, working directory setter, struct sizes).
• Refresh schema / generated wire docs / SDK docs and tests to remove version-pinned wording and reflect the new consumption model.

Reviewed changes

Copilot reviewed 13 out of 16 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/core/wxc_common/src/wire.rs	Updates WSLC port_mappings docstring to remove the old “vendored 2.8.1” wording while keeping UDP limitation note.
src/core/wxc_common/src/config_parser.rs	Updates TCP-only/UDP-rejection comments and keeps the UDP rejection test aligned.
src/backends/wslc/common/src/wslc_bindings.rs	Updates SDK ABI details (opaque struct sizes, new component flag, renamed/updated function types, pull options field rename).
src/backends/wslc/common/src/wsl_container_runner.rs	Switches preflight from WslcCanRun to WslcGetMissingComponents, updates working directory setter name, and updates pull options field usage.
src/backends/wslc/common/build.rs	Downloads the .nupkg from the MxcDependencies feed, extracts it, and copies wslcsdk.dll next to the built binary; retains vendored fallback.
sdk/node/tests/integration/wslc-e2e.test.ts	Updates test comment wording about UDP limitation to avoid pinning to 2.8.1.
sdk/node/src/types.ts	Updates public SDK doc comments for WSLC port mappings to remove “vendored 2.8.1” wording.
sdk/node/src/generated/wire.ts	Regenerates/updates wire doc text for WSLC port mappings.
schemas/dev/mxc-config.schema.0.8.0-dev.json	Updates schema description text for WSLC port mappings to remove “vendored 2.8.1” wording.
external/wslc-sdk/README.md	Documents the new feed-based resolution order, version pin location, and update process.
docs/wsl/wsl-container-support-plan.md	Updates WSLC SDK version and consumption description (but still contains some outdated API-name references).
docs/wsl/wsl-container-getting-started.md	Bumps documented WSL minimum/runtime expectation to 2.9.3+.
docs/schema.md	Updates example comment wording around WSLC UDP limitation to remove “vendored 2.8.1”.
docs/linux-wsl-roadmap-june-2026.md	Updates wording around UDP limitation to remove “Microsoft.WSL.Containers 2.8.1” mention.

Comments suppressed due to low confidence (1)

docs/wsl/wsl-container-support-plan.md:200

• This section still lists WslcCanRun() as the preflight API, but the implementation has switched to WslcGetMissingComponents(). Updating this keeps the support plan aligned with the current code and SDK surface.

Rust FFI declarations for the WSLC SDK C API (v2.9.3). Hand-written `extern "C"`
blocks from `wslcsdk.h`. Key bindings (actual API names from the SDK):

Session APIs:
- `WslcCanRun()` — preflight: check if WSLC runtime is available

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.