Function extract_first_prompt

src/command_system/export_command.py:95–129

First user message's first line, truncated to 50 chars (export.tsx:20-42). Mirrors TS ``msg.message?.content`` reads via the renderer's :func:`extract_message_content` accessor so flat dataclasses and wire-shaped dicts both resolve.

(messages: Any)

def extract_first_prompt(messages: Any) -> str:
    """First user message's first line, truncated to 50 chars (export.tsx:20-42).

    Mirrors TS ``msg.message?.content`` reads via the renderer's
    :func:`extract_message_content` accessor so flat dataclasses and wire-shaped
    dicts both resolve.
    """
    first_user = None
    for msg in messages or []:
        if _message_type(msg) == "user":
            first_user = msg
            break
    if first_user is None:
        return ""

    content = extract_message_content(first_user)
    result = ""
    if isinstance(content, str):
        result = content.strip()
    elif isinstance(content, list):
        # TS uses ``find(b => b.type === 'text')`` and reads ``.text`` off the
        # match; a malformed first text block (no ``text`` key) yields ``''``.
        # ``is_text_block`` additionally requires a string ``text``, so a
        # malformed block is skipped and scanning continues — a negligible
        # divergence (TextBlock.text is typed ``str = ""``, so unreachable in
        # practice) that fails no worse than TS.
        for item in content:
            if is_text_block(item):
                result = _block_text(item).strip()
                break

    result = result.split("\n")[0]
    if len(result) > 50:
        result = result[:49] + "…"
    return result


def sanitize_filename(text: str) -> str: