Add MSBuild workflow for CI/CD

[nsabedra27-glitch]

This workflow automates the build process using MSBuild on push and pull request events for the master branch.

Important

26.06 FREEZE April 30th: Non-bugfix PRs not ready by this date will wait for 26.09.

RC1 is scheduled on May 14th

The final release is scheduled for June 1st.

Checklist

Before submitting the PR, ensure the following tasks are completed. If an item is not applicable to your PR, please mark it as checked:

• The changelog has been updated in the relevant commit(s) according to the guidelines.
• Tests have been added or modified to reflect the changes.
• Documentation has been reviewed and updated as needed.
• Related issues have been listed and linked, including any that this PR closes.
• Important All PRs must consider how to reverse any persistent changes for tools/lightning-downgrade

[Andezion]

Core-lightning built via the custom configurator/waf-based build system (see ccan/config.h, configurator.out in the working tree) - there is no .sln file and no MSBuild/.NET tooling anywhere in this repo. This workflow will fail on the very first step - no NuGet packages or project files exist and no solution file to build. What is this workflow meant to build? There's no indication the project has an MSBuild-based component

[Andezion]

Irrelevant cost/runtime for a project that has nothing to do with Windows/.NET builds