PRD 0020 chunk 3. Enter on a focused agents-pane row drops to a
claude session inside the selected bottle. Works for both
dashboard-owned bottles (looks up the stored Bottle handle in
the main loop's `bottles` dict) and externally-discovered ones
(synthesizes a DockerBottle from the slug → `claude-bottle-<slug>`
container name).
For the synthesized path, the `--append-system-prompt-file`
target resolves via metadata.json + the manifest's agent prompt
if both can be read; otherwise the re-attach runs without the
flag (claude defaults to no system prompt, the bottle's other
state is untouched).
Shares the curses.endwin → attach → refresh handoff with the
chunk-2 new-agent flow via a new `_attach_to_bottle` helper.
Footer reshuffled to advertise `[Enter] view/attach`. 464 unit
tests pass (3 new for `_bottle_for_slug`).
didericis