feat: 重新设计“帮我写清楚”弹框

- 标题从“调教提示词”改成“帮我把要求写清楚”，开头说明怎么用
- 学生每次发的标成“你的要求 · 第 N 版”，AI 的回复标成“AI 的建议”
- 输入框明确是“你的要求”；按钮改成“让 AI 再看看”和“用这段生成网页”，
  没改过的要求不会重复发；AI 回复时不能直接生成

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/src/components/ai/GuidancePanel.vue

@@ -2,83 +2,75 @@
   <n-modal
     :show="isOpen"
     preset="card"
-    title="调教提示词"
-    style="width: min(560px, 92vw)"
+    title="帮我把要求写清楚"
+    style="width: min(640px, 92vw)"
     :mask-closable="!streaming"
     @update:show="onModalClose"
   >
-    <div class="guidance-body">
-      <div class="guidance-messages" ref="messagesRef">
-        <div
-          v-for="(msg, i) in messages"
-          :key="msg.id ?? i"
-          class="guidance-msg"
-          :class="msg.role"
-        >
-          <div class="msg-role">{{ msg.role === "user" ? "你" : "AI" }}</div>
-          <div class="msg-content" v-html="renderMarkdown(msg.content)"></div>
+    <p class="intro">
+      AI 会看看你的要求哪里还不够清楚，给你提建议。照着建议改好下面的要求，再让它看看；
+      觉得可以了就点“用这段生成网页”。
+    </p>
+
+    <div ref="messagesRef" class="messages">
+      <div v-for="(msg, i) in messages" :key="msg.id ?? i" :class="['msg', msg.role]">
+        <div class="who">
+          {{ msg.role === "user" ? `你的要求 · 第 ${versionOf(i)} 版` : "AI 的建议" }}
+        </div>
+        <div class="content markdown-body" v-html="renderMarkdown(msg.content)"></div>
       </div>
 
-        <div v-if="streaming" class="guidance-msg assistant">
-          <div class="msg-role">AI</div>
-          <div v-if="!displayStreamingContent" class="typing-indicator">
+      <div v-if="streaming" class="msg assistant">
+        <div class="who">AI 的建议</div>
+        <div v-if="!displayStreamingContent" class="typing">
           <span></span><span></span><span></span>
         </div>
         <div
           v-else
-            class="msg-content"
+          class="content markdown-body"
           v-html="renderMarkdown(displayStreamingContent)"
         ></div>
       </div>
     </div>
 
-      <div v-if="isReady" class="ready-hint">
+    <div v-if="isReady" class="ready">
       <Icon icon="lucide:check-circle" :width="16" />
-        提示词已优化，可以生成代码了！
+      AI 觉得要求已经写清楚了，可以生成网页了
     </div>
 
-      <div class="guidance-input">
+    <div class="draft">
+      <div class="draft-label">你的要求</div>
       <n-input
         v-model:value="draftPrompt"
         type="textarea"
-          :autosize="{ minRows: 2, maxRows: 5 }"
-          placeholder="修改你的提示词后发送..."
+        :autosize="{ minRows: 3, maxRows: 6 }"
+        placeholder="按 AI 的建议把要求改得更具体：要什么内容、什么颜色和布局、点了以后会怎样……"
         :disabled="streaming"
         @keydown.enter.exact.prevent="send"
       />
-        <n-flex justify="space-between" align="center" style="margin-top: 8px">
-          <div>
-            <n-button
-              v-if="streaming"
-              type="error"
-              size="small"
-              @click="stopGuidance"
-            >
-              停止
-            </n-button>
+      <n-flex justify="space-between" align="center" class="draft-actions">
+        <n-flex align="center" :size="8">
+          <n-button v-if="streaming" size="small" @click="stopGuidance">停止</n-button>
           <n-button
             v-else
             size="small"
-              :disabled="!draftPrompt.trim() || !connected"
+            :disabled="!draftPrompt.trim() || !connected || draftPrompt.trim() === lastSent"
             @click="send"
           >
-              发送
+            让 AI 再看看
           </n-button>
-          </div>
+          <span class="muted">Enter 发送，Shift + Enter 换行</span>
+        </n-flex>
         <n-button
           :type="isReady ? 'primary' : 'default'"
-            size="small"
-            :disabled="!draftPrompt.trim()"
+          :disabled="!draftPrompt.trim() || streaming"
           @click="generate"
         >
-            <template #icon>
-              <Icon icon="lucide:play" :width="14" />
-            </template>
-            生成代码
+          <template #icon><Icon icon="lucide:play" :width="14" /></template>
+          用这段生成网页
         </n-button>
       </n-flex>
     </div>
-    </div>
   </n-modal>
 </template>
 
@@ -106,13 +98,23 @@ const emit = defineEmits<{
 const draftPrompt = ref("")
 const messagesRef = ref<HTMLElement>()
 
+// 第几版要求：只数学生发的
+function versionOf(index: number) {
+  return messages.value.slice(0, index + 1).filter((m) => m.role === "user").length
+}
+
+// 没改过就不用再发一遍
+const lastSent = computed(
+  () => [...messages.value].reverse().find((m) => m.role === "user")?.content.trim() ?? "",
+)
+
 const displayStreamingContent = computed(() =>
   streamingContent.value.replace(/^\[READY\]\n?/, "")
 )
 
 function send() {
   const text = draftPrompt.value.trim()
-  if (!text || streaming.value) return
+  if (!text || streaming.value || text === lastSent.value) return
   sendGuidance(text)
 }
 
@@ -141,87 +143,113 @@ watch([() => messages.value.length, streamingContent], () => {
 </script>
 
 <style scoped>
-.guidance-body {
-  display: flex;
-  flex-direction: column;
-  gap: 12px;
+.intro {
+  margin: 0 0 12px;
+  font-size: 13px;
+  line-height: 1.7;
+  color: var(--wp-muted);
 }
 
-.guidance-messages {
-  min-height: 160px;
-  max-height: 360px;
+.messages {
+  min-height: 120px;
+  max-height: 45vh;
   overflow-y: auto;
   display: flex;
   flex-direction: column;
   gap: 12px;
+  padding-right: 4px;
 }
 
-.guidance-msg .msg-role {
-  font-size: 12px;
-  font-weight: bold;
+.who {
   margin-bottom: 4px;
+  font-size: 12px;
+  font-weight: 600;
   color: var(--wp-muted);
 }
 
-.guidance-msg.user .msg-role {
-  color: var(--wp-css);
-}
-
-.guidance-msg.assistant .msg-role {
+.msg.assistant .who {
   color: var(--wp-brand);
 }
 
-.guidance-msg.assistant .msg-content {
-  background: var(--wp-css-soft);
-  border-left: 3px solid var(--wp-css);
+.content {
   padding: 8px 12px;
-  border-radius: 0 6px 6px 0;
+  border-radius: 8px;
   font-size: 14px;
-  line-height: 1.6;
-}
-
-.guidance-msg.user .msg-content {
-  font-size: 14px;
-  line-height: 1.6;
+  line-height: 1.7;
   color: var(--wp-ink);
 }
 
-.msg-content :deep(p) {
-  margin: 0;
+.msg.user .content {
+  border: 1px solid var(--wp-line);
+  background: var(--wp-paper);
 }
 
-.ready-hint {
+.msg.assistant .content {
+  border-left: 3px solid var(--wp-brand);
+  border-radius: 0 8px 8px 0;
+  background: var(--wp-brand-soft);
+}
+
+.content :deep(p) {
+  margin: 0 0 6px;
+}
+
+.content :deep(:last-child) {
+  margin-bottom: 0;
+}
+
+.ready {
   display: flex;
   align-items: center;
   gap: 6px;
-  color: var(--wp-brand);
-  font-size: 13px;
-  font-weight: 500;
+  margin-top: 12px;
   padding: 6px 10px;
-  background: var(--wp-brand-soft);
   border-radius: 6px;
-  border: 1px solid var(--wp-brand-soft);
+  font-size: 13px;
+  color: var(--wp-brand);
+  background: var(--wp-brand-soft);
 }
 
-.typing-indicator {
+.draft {
+  margin-top: 14px;
+  padding-top: 12px;
+  border-top: 1px solid var(--wp-line);
+}
+
+.draft-label {
+  margin-bottom: 6px;
+  font-size: 13px;
+  font-weight: 600;
+}
+
+.draft-actions {
+  margin-top: 8px;
+}
+
+.muted {
+  font-size: 12px;
+  color: var(--wp-faint);
+}
+
+.typing {
   display: flex;
   gap: 5px;
-  padding: 8px 0;
+  padding: 10px 12px;
 }
 
-.typing-indicator span {
+.typing span {
   width: 7px;
   height: 7px;
   border-radius: 50%;
-  background: var(--wp-css);
+  background: var(--wp-brand);
   animation: bounce 1.4s ease-in-out infinite;
 }
 
-.typing-indicator span:nth-child(2) {
+.typing span:nth-child(2) {
   animation-delay: 0.2s;
 }
 
-.typing-indicator span:nth-child(3) {
+.typing span:nth-child(3) {
   animation-delay: 0.4s;
 }