Automatically upload new releases to GitHub

[okramarenko]

No description provided.

[cursor]

PR Summary

Medium Risk
Publish workflow now pushes to GitHub Releases with elevated contents: write permissions; mis-tagged pushes or bad VersionHistory sections could create incorrect draft releases, though NuGet publish behavior is unchanged aside from stricter tag matching.

Overview
Extends the existing tag-triggered publish workflow so that after NuGet push it also creates a draft GitHub Release with build artifacts attached.

The publish job now runs only for tags starting with refs/tags/v, uses a stricter semver tag filter on push, and grants contents: write for release creation. Release notes are sliced from the matching ### X.Y.Z section in docs/VersionHistory.md (via awk) and passed to softprops/action-gh-release@v2 as a draft for manual review before publishing.

README adds a short “Release process” section pointing to new RELEASE.md, which documents prerequisites (CONNECTOR_VERSION, README title, VersionHistory.md), tagging (vX.Y.Z), automated NuGet + draft release steps, verification, and handling failed or already-published releases.

^{Reviewed by Cursor Bugbot for commit c4f96e6. Configure here.}