refactor(agent): use agent-neutral runtime names

Assisted-by: Codex

docs/prds/0021-dashboard-tmux-split-pane.md

@@ -163,7 +163,7 @@ def _attach_in_tmux(bottle, slug, *, resume) -> str:
 
 The non-tmux path is unchanged from PRD 0020 — `_attach_via_
 handoff` is what those two flows already do today (curses.
-endwin → attach_claude → stdscr.refresh).
+endwin → attach_agent → stdscr.refresh).
 
 ### Pane creation
 
@@ -230,10 +230,10 @@ def _tmux_pane_exists(pane_id) -> bool:
 
 The tmux helpers need the full docker-exec argv for claude —
 specifically including the `--append-system-prompt-file <path>`
-flag that `DockerBottle.exec_claude` appends today when the
-bottle has a prompt path. Refactor: split `exec_claude` into a
+flag that `DockerBottle.exec_agent` appends today when the
+bottle has a prompt path. Refactor: split `exec_agent` into a
 pure `claude_docker_argv(args, *, tty)` that returns the argv
-and a thin `exec_claude` that calls `subprocess.run` on it.
+and a thin `exec_agent` that calls `subprocess.run` on it.
 Both the tmux path AND the existing foreground path use the
 same argv builder.
 
@@ -272,7 +272,7 @@ Three failure modes worth handling:
 Sized small.
 
 1. **`claude_docker_argv` refactor.** Pure-ish split of
-   `DockerBottle.exec_claude` so both foreground and tmux
+   `DockerBottle.exec_agent` so both foreground and tmux
    paths build on the same argv. No behavior change for the
    existing tests.
 2. **tmux helpers + pane state.** Add `_in_tmux`,