ci(release): release only from main - #167

This pull request removes the reviewed-epic release path from the workflow and rewrites the accompanying Python script so it asserts the removed mode stays gone. The new assertions (`test_a_dispatch_names_only_a_tag_and_runs_only_the_module_release`, `test_release_is_the_registered_tag_workflow`) can fail if any of the removed inputs, jobs, or the reviewed-release `uses:` line returns, and the deleted validator tests are deleted together with the function they exercised, so nothing is left asserting on a mock. No behavioural gap I can anchor in the diff. _The code index is behind this pull request (indexed at `9ff6db68717d`), so retrieved context may be out of date._

No findings.