Introduce a new `split` GitHub Actions workflow that runs on `v*` tags, gates on the test workflow, and then executes a new `.github/split.sh` script to split each component package into `general-purpose-io/*` repos with matching branches and tags. The script adds manifest/version/branch-alias dependency checks, line-branch creation/fast-forward logic, and remote reachability checks before publishing. Also update `tests.yml` for `workflow_call`, document the release process in `.okf/releasing.md` (plus index/log updates), and bump all component `dev-main` branch aliases from `0.9.x-dev` to `0.10.x-dev`.