VSC: Marketplace publishing pipeline

[Hmbown]

Summary

CI builds .vsix on tag and publishes to VS Code Marketplace plus OpenVSX.

Acceptance criteria

• GitHub Action publishes on vscode-v*.. tag.
• Uses repo secrets.

Files

.github/workflows/vscode.yml

Size

S

Source

Source tag: VSC. Add exact upstream/opencode source links during implementation if they are not already known. Do not copy external code blindly; port the behavior into this repo's architecture.

Filed from 2026-05-02 v0.8.8 intake.