fix(doubao): adapt to 2026-07 DOM refactor

[RusianHu]

Problem

The doubao adapter is broken against Doubao's 2026-07 web refactor: ask, read, detail, and history all fail. The refactor removed data-testid attributes and renamed several CSS classes, so the adapter's selectors no longer match.

Symptoms on opencli v1.8.6:

• doubao ask → Could not find Doubao input element (composer selector stale)
• doubao read → No visible Doubao messages were found (message-list selector stale)
• doubao history → No conversation history found (sidebar selector stale)
• doubao detail → No messages found. Verify the conversation ID. (detail script stale)

Root cause

1. Composer: input is now a Semi Design <textarea class="semi-input-textarea"> with placeholder 发消息或按住空格说话...; data-testid="chat_input_input" was removed.
2. Message list: container class is now list_items (previously matched via [class*="message-list-"] etc.).
3. Sidebar: data-testid="flow_chat_sidebar" / chat_list_thread_item removed; sidebar now uses left-side-/w-sidebar-width classes, thread items are a[href*="/chat/"].
4. Visibility check: the browser bridge operates on a 0x0/background tab where getBoundingClientRect().width === 0 for every element, so isVisible's width > 0 && height > 0 rejected everything — including the composer and message items that are nonetheless present and usable/readable.

Changes (clis/doubao/utils.js)

• Composer selectors: prepend textarea.semi-input-textarea and textarea[placeholder*="发消息"].
• isVisible (composer + getTurnsScript): relax width > 0. In a 0x0/background tab elements have zero width but are still present and readable; require height > 0 (composer) or drop the size check (message turns). display:none / visibility:hidden / hidden are still filtered.
• getTurnsScript: add [class*="list_items"] to message-list selectors so messages are read via structured turns (clean) instead of falling back to the noisy transcript.
• getTranscriptLinesScript: scope to the main chat area (sidebar's sibling) and strip header (title + disclaimer), input area (buttons), and follow-up suggestion chips, so the transcript fallback stays clean.
• getConversationListScript (history): sidebar via [class*="left-side-"], [class*="w-sidebar-width"], thread items via a[href*="/chat/"].
• getConversationDetail (detail): reuse getDoubaoVisibleTurns; the old data-testid-based detail script is fully stale.
• prepareDoubaoComposerScript: include viewport/url/textarea details in the failure reason to aid future debugging.

Verification

End-to-end on opencli v1.8.6 against current doubao web (2026-07):

Command	Result
doubao status	✅ Connected
doubao history	✅ lists 20 conversations
doubao detail <id>	✅ clean User/Assistant turns, no sidebar/follow-up noise
doubao read	✅ reads current conversation
doubao new	✅ creates new conversation
doubao ask "1加1等于几？请只回答数字"	✅ returns clean 2, no noise

• Existing doubao unit tests: 32/32 pass (npx vitest run clis/doubao/)
• npx tsc --noEmit: pass

Notes

• The 0x0-viewport visibility issue is worth highlighting: it affects any adapter whose bridge tab is backgrounded/minimized. The relaxation here is scoped to doubao's composer + turns isVisible, so it should not affect other adapters.
• Selector changes are additive (nothing removed) to preserve the 2026-05 fallback paths and existing unit-test fixtures.