Module pr 

GitHub PR helpers using the gh CLI.

Responsibilities:

• Expose the crate-facing PR operations and status types.
• Keep the public surface stable while delegating execution/parsing to focused submodules.
• Colocate PR-specific tests near the implementation.

Not handled here:

• Task selection or worker execution (see commands::run::parallel).
• Direct-push parallel integration logic (see commands::run::parallel::integration).

Invariants/assumptions:

• gh is installed and authenticated for command execution paths.
• Repo root points to a GitHub-backed repository.