chore: update CI workflow and release process

- Replaced `@semantic-release/git` with `@semantic-release/exec` for handling release commands.
- Updated `.releaserc.json` to reflect changes in release command execution.
- Modified CI workflow to streamline the release process, including tagging and Docker image publishing.
- Removed obsolete publish workflow and integrated its functionality into the main CI workflow.
- Enhanced documentation to clarify the new release process and CI pipeline structure.

README.md

@@ -50,6 +50,6 @@ docker compose --profile reference up -d
 
 - [docs/releasing.md](docs/releasing.md) — пайплайн, commit conventions, секреты CI
 - API: `GET /version` и `GET /v1/version` (поле `version`)
-- Docker-образы публикуются по git-тегу `vX.Y.Z` (workflow **Publish**)
+- Docker-образы: теги `latest`, `vX.Y.Z`, `X.Y.Z` — в **том же CI run**, что и релиз (job `release`)
 
 Лицензия и условия использования — по политике владельца репозитория.