feat: enhance floating mini timer with controls and pop-out button

MiniTimer shows project color dot, name, elapsed time, stop button,
and expand-to-main button. Timer.vue has pop-out button when running.

src/views/MiniTimer.vue

@@ -1,27 +1,55 @@
-<template>
-  <div class="mini-timer flex items-center justify-center h-screen bg-bg-base select-none" style="-webkit-app-region: drag">
-    <div class="text-center">
-      <p class="text-[2rem] font-medium font-[family-name:var(--font-heading)] tracking-tighter text-text-primary">
-        {{ timerStore.formattedTime }}
-      </p>
-      <p v-if="projectName" class="text-[0.6875rem] text-text-tertiary mt-1 truncate max-w-[180px]">
-        {{ projectName }}
-      </p>
-    </div>
-  </div>
-</template>
-
 <script setup lang="ts">
 import { computed } from 'vue'
+import { invoke } from '@tauri-apps/api/core'
 import { useTimerStore } from '../stores/timer'
 import { useProjectsStore } from '../stores/projects'
+import { Square, Maximize2 } from 'lucide-vue-next'
 
 const timerStore = useTimerStore()
 const projectsStore = useProjectsStore()
 
 const projectName = computed(() => {
-  if (!timerStore.selectedProjectId) return ''
-  const project = projectsStore.projects.find(p => p.id === timerStore.selectedProjectId)
-  return project?.name || ''
+  if (!timerStore.selectedProjectId) return 'No project'
+  return projectsStore.projects.find(p => p.id === timerStore.selectedProjectId)?.name || 'Unknown'
 })
+
+const projectColor = computed(() => {
+  if (!timerStore.selectedProjectId) return '#6B7280'
+  return projectsStore.projects.find(p => p.id === timerStore.selectedProjectId)?.color || '#6B7280'
+})
+
+async function stopTimer() {
+  await timerStore.stop()
+}
+
+async function expandToMain() {
+  try {
+    await invoke('close_mini_timer')
+  } catch (e) {
+    console.error(e)
+  }
+}
 </script>
+
+<template>
+  <div class="h-full w-full flex items-center gap-3 px-4 bg-bg-base select-none" style="-webkit-app-region: drag">
+    <span class="w-2.5 h-2.5 rounded-full shrink-0" :style="{ backgroundColor: projectColor }" />
+    <span class="text-[0.75rem] text-text-primary truncate flex-1">{{ projectName }}</span>
+    <span class="text-[1rem] font-mono text-accent-text font-medium tracking-tight">{{ timerStore.formattedTime }}</span>
+    <div class="flex items-center gap-1" style="-webkit-app-region: no-drag">
+      <button
+        v-if="timerStore.isRunning"
+        @click="stopTimer"
+        class="w-6 h-6 flex items-center justify-center rounded-full bg-status-error hover:bg-status-error/80 transition-colors"
+      >
+        <Square class="w-2.5 h-2.5 text-white" fill="white" />
+      </button>
+      <button
+        @click="expandToMain"
+        class="w-6 h-6 flex items-center justify-center rounded text-text-tertiary hover:text-text-secondary transition-colors"
+      >
+        <Maximize2 class="w-3 h-3" />
+      </button>
+    </div>
+  </div>
+</template>