## Why?
The Codex App already exposes branch and PR context in its
branch-details UI. This brings the same context into the CLI footer as
opt-in statusline items, so users can choose the extra signal without
making the default footer busier.
## What?
Add optional `pull-request-number` and `branch-changes` items to the
configurable TUI status line.
- `pull-request-number` shows the open PR for the current checkout and
renders as a clickable terminal hyperlink when OSC 8 links are
supported.
- `branch-changes` shows committed additions/deletions against the
repository default branch, or `No changes` when the branch has no
committed diff.
<img width="1257" height="261" alt="CleanShot 2026-05-03 at 20 44 15"
src="https://github.com/user-attachments/assets/10b4380b-c3e9-4729-9ee1-3f742068fa47"
/>
## Architecture
This follows the same client/app-server split as the Codex App: the TUI
owns presentation, caching, and optional rendering, while
workspace-sensitive `git` and `gh` discovery runs through app-server.
The new TUI-local `workspace_command` layer sends bounded,
non-interactive `command/exec` requests to the active app-server. That
makes the implementation remote-friendly: the TUI does not decide
whether commands run in an embedded local workspace or a remote
workspace, and it does not bypass app-server sandbox or permission
policy.
The branch summary logic stays internal to `codex-tui` because this PR
only needs TUI statusline behavior. The command boundary is still
isolated behind `WorkspaceCommandExecutor`, so the lookup code can be
lifted or reused later without changing statusline rendering.
## How?
- Add a TUI `WorkspaceCommandExecutor` abstraction backed by app-server
`command/exec`.
- Add branch summary probes for:
- current branch name,
- open PR metadata,
- committed branch diff stats against the default branch.
- Prefer remote-tracking default branch refs for diff stats, avoiding
stale or absent local `main` branches.
- Resolve PRs with `gh pr view` first, then fall back to
commit-associated PR lookup across parent/fork repos.
- Add `/statusline` picker entries, preview values, rendering, and OSC 8
clickable PR links.
- Keep all probes best-effort so missing `git`, missing `gh`, auth
failures, or non-git directories hide optional items instead of
surfacing footer errors.
## Validation
- `cargo test -p codex-tui branch_summary -- --nocapture`
- Snapshot coverage for the `/statusline` preview/setup rendering paths
- Hyperlink rendering coverage for clickable PR statusline cells
Felipe Coury