[Bug] TUI: folded assistant messages ("… N messages") are disposed and cannot be re-expanded — previous replies become invisible

What version of Kimi Code is running?

0.36.0

Which open platform/subscription were you using?

Kimi Code (OAuth)

Which model were you using?

K3-256k (thinking: high)

What platform is your computer?

Linux 6.19.8-arch1-3-surface x86_64

What issue are you seeing?

When a turn ends, the TUI folds all but the last 2 assistant messages of that turn into a muted summary line, e.g.:

✨ <assistant reply>
… 1 messages

Once the next turn starts, the folded assistant reply is no longer visible anywhere in the transcript. Pressing Ctrl+O (expand tool output) only reveals thinking blocks and tool calls — it does not bring back the folded assistant message.

The only ways to read the hidden reply are /export-md or the raw wire.jsonl, and the only way to prevent the folding is restarting with KIMI_CODE_TUI_KEEP_RECENT_ASSISTANT_COMPLETED=0.

What steps can reproduce the bug?

1. Start a session and have a conversation where a single turn produces 3+ assistant messages (e.g. several Q&A evaluations in one turn).
2. Send another prompt so that turn completes.
3. Scroll up: earlier assistant messages of the completed turn are replaced by … N messages.
4. Press Ctrl+O — thinking/tool output expands, the folded assistant messages do not.

What is the expected behavior?

Folded assistant messages should be viewable without leaving the TUI — e.g. the … N messages summary line should be expandable via Ctrl+O (like thinking/tool output), or assistant message text should be excluded from the completed-turn folding so only thinking/tool steps fold.

Additional information

The folding itself (bounding the mounted component tree) is a reasonable memory optimization — the problem is that the folded reply text has no in-TUI escape hatch, unlike thinking traces and tool output. Related: #2296 (scroll position issues when reading earlier messages).

Start with foldCurrentTurnContent() in apps/kimi-code/src/tui/utils/transcript-window.ts and toggleToolOutputExpansion() in apps/kimi-code/src/tui/kimi-tui.ts. Reproduce the issue with a turn producing 3+ assistant messages, then trace how StepSummaryComponent and disposed components are handled. Done means folded assistant replies can be viewed again in the live TUI without relying on /export-md or wire.jsonl.