ui: add workflow status badge + last activity indicator in log header

- Shows planning/executing/done/failed/waiting badge with pulse animation
- Shows relative time since last activity (e.g. "30s 前")

web/src/components/ExecutionSection.vue

@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { ref, computed, watch, nextTick } from 'vue'
+import { ref, computed, watch, nextTick, onMounted, onUnmounted } from 'vue'
 import type { ExecutionLogEntry, Comment, LlmCallLogEntry } from '../types'
 
 const basePath = import.meta.env.BASE_URL.replace(/\/$/, '')
@@ -35,6 +35,40 @@ function quoteLlmCall(e: Event, lc: LlmCallLogEntry) {
   emit('quote', `[LLM] ${preview}`)
 }
 
+// Last activity relative time
+const now = ref(Date.now())
+let ticker: ReturnType<typeof setInterval> | null = null
+onMounted(() => { ticker = setInterval(() => { now.value = Date.now() }, 5000) })
+onUnmounted(() => { if (ticker) clearInterval(ticker) })
+
+const lastActivityAgo = computed(() => {
+  if (props.workflowStatus === 'done' || props.workflowStatus === 'failed') return ''
+  const times = [
+    ...props.entries.map(e => e.created_at),
+    ...props.llmCalls.map(l => l.created_at),
+  ].filter(Boolean)
+  if (!times.length) return ''
+  const latest = times.reduce((a, b) => a > b ? a : b)
+  const d = new Date(latest.includes('T') ? latest : latest + 'Z')
+  const secs = Math.floor((now.value - d.getTime()) / 1000)
+  if (secs < 5) return '刚刚'
+  if (secs < 60) return `${secs}s 前`
+  const mins = Math.floor(secs / 60)
+  if (mins < 60) return `${mins}m 前`
+  return `${Math.floor(mins / 60)}h 前`
+})
+
+const workflowStatusLabel = computed(() => {
+  switch (props.workflowStatus) {
+    case 'planning': return '规划中'
+    case 'executing': return '执行中'
+    case 'done': return '已完成'
+    case 'failed': return '失败'
+    case 'waiting_approval': return '等待确认'
+    default: return props.workflowStatus
+  }
+})
+
 const scrollContainer = ref<HTMLElement | null>(null)
 const userScrolledUp = ref(false)
 const detailedMode = ref(false)
@@ -177,6 +211,9 @@ watch(logItems, () => {
   <div class="execution-section" ref="scrollContainer" @scroll="onScroll">
     <div class="section-header">
       <h2>日志</h2>
+      <span v-if="workflowStatus && workflowStatus !== 'pending'" class="workflow-badge" :class="workflowStatus">{{ workflowStatusLabel }}</span>
+      <span v-if="lastActivityAgo" class="last-activity">{{ lastActivityAgo }}</span>
+      <span class="header-spacer" />
       <label class="detail-toggle">
         <input type="checkbox" v-model="detailedMode" />
         <span>详细</span>
@@ -274,6 +311,51 @@ watch(logItems, () => {
   letter-spacing: 0.5px;
 }
 
+.header-spacer {
+  flex: 1;
+}
+
+.workflow-badge {
+  font-size: 11px;
+  font-weight: 600;
+  padding: 2px 10px;
+  border-radius: 10px;
+  letter-spacing: 0.3px;
+}
+
+.workflow-badge.planning,
+.workflow-badge.executing {
+  background: var(--accent);
+  color: var(--bg-primary);
+  animation: pulse-badge 2s ease-in-out infinite;
+}
+
+.workflow-badge.done {
+  background: var(--success);
+  color: #fff;
+}
+
+.workflow-badge.failed {
+  background: var(--error);
+  color: #fff;
+}
+
+.workflow-badge.waiting_approval {
+  background: #ff9800;
+  color: #fff;
+}
+
+.last-activity {
+  font-size: 11px;
+  color: var(--text-secondary);
+  opacity: 0.7;
+}
+
+@keyframes pulse-badge {
+  0%, 100% { opacity: 1; }
+  50% { opacity: 0.6; }
+}
+
 .detail-toggle {
   display: flex;
   align-items: center;