feat(keyboard): ship AI hint carousel, home library cards, and clipboard polish

Rotate AI idle suggestions with optional remote packs, move history/dictionary onto self-sizing Home preview cards, harden clipboard capture/prompting, and simplify keyboard chrome by dropping most liquid-glass shadows.

CHANGELOG.md

@@ -8,23 +8,36 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
-- **Clipboard history**: optional keyboard clipboard history (latest 15 plain-text items, App Group local), top-bar clipboard entry, history panel with whitespace token chips, and a suggestion strip across voice / typing / AI when enabled. / **剪贴板历史**：可选的键盘剪贴板历史（最近 15 条纯文本、App Group 本地），顶栏剪贴板入口、带空白分词芯片的历史面板，以及开启后在语音 / 打字 / AI 面显示的建议条。
+- **AI idle hint carousel**: AI mode empty state rotates one-line suggestions (local evergreen + optional remote hot topics); tap sends the card prompt to the LLM without the mic. Coexists with the clipboard suggestion strip in the top bar. / **AI 空闲建议轮播**：AI 模式空状态轮播单行建议（内置常驻 + 可选远程热点）；点按即跳过麦克风把卡片 prompt 发给模型。与顶栏剪贴板建议条并存。
+- **Hint feed refresh**: main app silently fetches `https://key.osglab.com/hints` about every 12 hours, compresses titles with the user’s polish LLM, and writes App Group ready packs for the keyboard. / **建议源刷新**：主 App 约每 12 小时静默拉取 `https://key.osglab.com/hints`，用用户润色 LLM 压缩标题，写入 App Group 供键盘只读。
+- **Clipboard history**: optional keyboard clipboard history (latest 15 plain-text items, App Group local), top-bar clipboard entry, history panel with whitespace token chips, and a suggestion strip across voice / typing / AI when enabled. Within ~30s of a copy, AI idle hints can prefer clipboard-related cards. / **剪贴板历史**：可选的键盘剪贴板历史（最近 15 条纯文本、App Group 本地），顶栏剪贴板入口、带空白分词芯片的历史面板，以及开启后在语音 / 打字 / AI 面显示的建议条；复制后约 30 秒内 AI 空闲建议可偏向剪贴板相关卡片。
 - **Clipboard settings**: Settings home adds a Clipboard page under AI Agent with History and Suggestion-strip toggles (both default off); keyboard deep-links open that page. / **剪贴板设置**：设置首页在 AI Agent 下方新增「剪贴板」页，含历史记录与候选栏展示开关（均默认关闭）；键盘可深链打开该页。
 - **Paste permission guidance**: the Clipboard settings page explains iOS's durable “Paste from Other Apps” permission and opens iOS Settings directly, so users can set it to Allow once and stop the per-copy paste prompt. / **粘贴授权引导**：剪贴板设置页说明 iOS 的「从其他 App 粘贴」持久授权并可直接跳转系统设置，用户设为「允许」一次即不再每次复制都弹窗。
 - **Clipboard settings copy**: shorten history, suggestion-strip, and paste-permission wording to brief user-facing lines. / **剪贴板设置文案**：精简历史、建议条与粘贴授权说明，改为简短面向用户的表述。
 - **Settings summary placement**: navigation-row summaries (AI Agent, Clipboard, etc.) sit trailing before the chevron, matching the Version row. / **设置摘要位置**：导航行摘要（AI Agent、剪贴板等）移到右侧 chevron 前，与「版本」行一致。
 - **AI answer streaming**: AI mode streams visible answer text into the keyboard as the model writes (all AI-mode transports), with throttled App Group updates, search-fallback draft restart, and a “thinking” status before the first token; dictation polish stays non-streaming. / **AI 回答流式输出**：AI 模式在模型开始写正文后将可见答案增量推送到键盘（覆盖全部 AI 传输路径），经 App Group 节流更新；搜索失败回退会清空半截草稿；首 token 前显示「思考中」；听写润色仍为整段返回。
+- **Spoken clipboard requests**: in AI mode, naming the clipboard out loud (“reply to the clipboard”, “translate my clipboard”) now attaches the stored clipboard text to that question. Naming it is the authorization, so no second confirmation appears; every other AI question is still sent without clipboard text, and with Clipboard History off the request fails with a clear reason instead of guessing. / **口述剪贴板指令**：AI 模式中说出「回复剪贴板」「把剪贴板翻译成英文」等，会把已保存的剪贴板正文附加到该问题。说出即视为授权，不再二次确认；其余 AI 提问一律不附带剪贴板；未开启剪贴板历史时会给出明确原因而非自行猜测。
 - **AI Agent settings**: Settings home adds an AI Agent row under General, with a Response length preference (Short / Medium / Detailed, default Medium). AI mode injects soft length guidance into the system prompt and syncs the choice via iCloud settings. / **AI Agent 设置**：设置首页在「通用」下方新增 AI Agent 入口，支持「回复篇幅」（简短 / 中等 / 详细，默认中等）。AI 模式将篇幅作为软约束写入 system prompt，并纳入 iCloud 设置同步。
 
 ### Changed
+- **Home library cards**: History and Personal dictionary leave the bottom dock; Home shows two self-sizing preview cards — transcripts split by hairlines (two lines each) and dictionary terms with their source/usage detail line — that push the existing pages with a standard back button. / **首页资料卡片**：历史记录与个性词库移出底部 Dock；首页改为两张按内容自适应高度的预览卡——历史条目用细线分隔（每条最多两行），词库显示词条与来源/使用次数小字——点按后以标准返回按钮进入原页面。
+- **Home scroll status**: engine and session status scroll with the page at the bottom (dock clearance via tab-bar padding) instead of a pinned footer. / **首页滚动状态**：引擎与会话状态随页面滚到底部（Dock 留白与设置页一致），不再钉在底部。
+- **Clipboard AI prompt contract**: clipboard text now reaches the model as a separate escaped `clipboard_text` block beside the instruction, and the AI system prompt treats that block as untrusted content instead of instructions. Hint cards carry only the instruction. / **剪贴板 AI 提示词契约**：剪贴板正文改为与指令并列的独立转义 `clipboard_text` 块，AI system prompt 明确将该块视为不可信内容而非指令；建议卡片只保留指令本身。
+- **Hint feed freshness**: refresh tracks success per locale (a Chinese success no longer masks an English failure), a manifest failure no longer aborts the packs, and a pack past its `expiresAt` — or older than 48 hours without one — falls back to the built-in evergreen catalog instead of showing stale hot topics. / **建议源新鲜度**：刷新按语言分别记录成功（中文成功不再掩盖英文失败），manifest 失败不再中断整轮；超过 `expiresAt`（或无该字段且超过 48 小时）的建议包回退到内置常驻卡片，不再展示陈旧热点。
+- **Privacy policy**: document AI idle suggestions, opt-in clipboard history (panel, suggestion strip, and AI hint use), and when clipboard text is sent to your AI provider. / **隐私政策**：补充 AI 空闲建议、可选剪贴板历史（面板、建议条与 AI 提示用途），以及剪贴板正文在何种情况下会发送给 AI 服务商。
 - **Clipboard history row opacity**: history panel entry cards use 50% surface opacity so the keyboard chrome shows through. / **剪贴板历史条目透明度**：历史面板每条记录背景改为 50% 透明度，键盘底色可透出。
 - **Translation button chrome**: voice mic-row translation control matches the adjacent undo key (44×44 rounded rectangle) instead of a circular chip. / **翻译按钮样式**：语音麦克风行的翻译控件改为与相邻撤销键一致的 44×44 圆角矩形，不再使用圆形芯片。
 - **Undo covers clipboard pastes**: the undo key now rolls back text inserted from the clipboard suggestion strip or history panel, in one step regardless of length. Pasted text stays out of dictation history and is never offered for last-input editing. / **撤销支持剪贴板粘贴**：撤销键现在可回滚从剪贴板建议条或历史面板插入的文字，无论长度都一次撤销到底。粘贴内容不进入听写历史，也不会成为「编辑上次输入」的对象。
 - **Undo key label**: rename the accessibility label from “Undo last dictation” to “Undo last input” now that it covers dictation, AI answers, edits and pastes. / **撤销键文案**：无障碍标签由「撤销上次听写」改为「撤销上次输入」，因其现已覆盖听写、AI 答案、编辑与粘贴。
 - **Translation chip placement**: move the top-bar translation control onto the voice mic row, mirrored with Undo; the top-bar slot becomes the clipboard button. / **翻译入口位置**：顶栏翻译控件移到语音麦克风行并与撤销对称；原顶栏位置改为剪贴板按钮。
-- **AI empty-state tip**: center “Tap the microphone to ask AI” in the answer area (horizontal + vertical). / **AI 空状态指引**：「点击麦克风向 AI 提问」在答案区域水平与垂直居中。
+- **AI empty-state tip**: center “Tap the microphone to ask AI” in the answer area (horizontal + vertical); idle state now rotates hint cards there. / **AI 空状态指引**：答案区域水平与垂直居中展示空闲建议轮播（替代静态「点击麦克风」文案）。
 
 ### Fixed
+- **Clipboard hints missed a fresh copy**: the AI idle carousel now refreshes from the clipboard store as soon as a copy is captured, instead of waiting for the next 4-second rotation or a re-entry into AI mode — the reason clipboard suggestions often never appeared inside their 30-second window. / **新复制无剪贴板建议**：AI 空闲轮播在采集到新复制时立即依据剪贴板刷新，不再等待下一次 4 秒轮换或重新进入 AI 模式——这正是 30 秒窗口内常常看不到剪贴板建议的原因。
+- **Reduce Motion froze hint data**: Reduce Motion now only stops the fade rotation. Cards still refresh, so a new copy appears and a card whose clipboard window closed leaves the carousel. / **Reduce Motion 冻结建议数据**：辅助功能「减弱动态效果」现在只停止渐隐轮换，数据仍会刷新：新复制会出现，剪贴板窗口关闭的卡片会退出轮播。
+- **Expired clipboard hint tap**: tapping a clipboard card after its 30-second window fails closed with a “copy the text again” message instead of sending the instruction with empty material. / **过期剪贴板建议点击**：超过 30 秒窗口后点击剪贴板卡片会明确提示重新复制，而不是把缺少材料的指令发出去。
+- **Blank keyboard on cross-device clipboard**: clipboard-history capture no longer reads `UIPasteboard` on the main thread or during the appear sequence — a Universal Clipboard item still being fetched from another device blocked the main thread for seconds, freezing the keyboard mid-presentation. Reads now run on a background queue, start on the first poll tick after the slide-in, and never overlap. / **跨设备剪贴板导致键盘空白**：剪贴板历史采集不再在主线程、也不再在键盘出现流程中读取 `UIPasteboard`——待从其他设备拉取的通用剪贴板内容会同步阻塞主线程数秒，使键盘卡在呈现过程中。读取改到后台队列、延后到滑入完成后的首次轮询，且不会重叠执行。
+- **Keyboard presentation height**: drop the `target − system encapsulated height` priming trick. It read the pre-presentation full-screen height (874 pt on an iPhone) rather than the keyboard slot, clamped our constraint to 0, and lost to the system's required constraint anyway; the surface is now bottom-anchored so a transient over-tall container can never park it above the visible slot. / **键盘呈现高度**：移除「目标高度 − 系统封装高度」的预置技巧。它读到的是呈现前的整屏高度（iPhone 上 874pt）而非键盘槽，把约束夹成 0，且本来就压不过系统的 required 约束；键盘内容改为底部锚定，容器临时过高时不会再被顶到可见区域之外。
 - **Undo of long insertions**: caret verification now compares the tail of the inserted text's last line instead of the whole string, so long or multi-line insertions no longer lose undo the moment the host returns a truncated context. / **长文本撤销**：光标校验改为比对插入文本最后一行的尾部而非整段，长文本或多行插入不再因宿主返回截断上下文而立刻失去撤销能力。
 - **Undo after editing last input**: a newer insertion now clears the pending edit transaction, so undo rolls back that insertion instead of deleting it and restoring the older edit's original text. / **编辑上次输入后的撤销**：新的插入会清除待撤销的编辑事务，撤销将回滚该次插入，而不再是删除它并还原上一次编辑前的旧文本。
 - **AI waiting spinner duplicate**: remove the mini ProgressView beside the AI status caption; the mic button spinner remains the sole loading indicator while recognizing or generating. / **AI 等待转圈重复**：去掉 AI 状态文案旁的迷你 ProgressView；识别/生成中仅保留麦克风按钮上的 loading。