Release validation tags should dispatch publish workflow automatically

[lucarlig]

Problem

When a PR with plugin version bumps merges to main, CI Rust Python Package Plugins creates release tags in create-release-tags. Those tags are pushed by workflow automation, so the Release Rust Python Package Plugin tag trigger does not reliably start publish runs.

Observed on PR #99: tags were created for the bumped plugins, but PyPI stayed on the previous versions until the release workflow was manually dispatched for each tag.

Expected

After release tags are created from the merge-to-main workflow, the release workflow should be dispatched automatically for each tag and publish to PyPI.

Scope

Update the tag creation workflow so merge-to-main release tags trigger the release workflow explicitly after successful tag creation. Keep PR release validation behavior unchanged.

Acceptance criteria

• Merging a version-bump PR creates tags as today.
• For each created/existing release tag, the workflow dispatches release-rust-python-package.yaml with repository=pypi.
• Dispatch happens only on main push release-tag creation, not during PR validation.
• CI validates the workflow change.