Initial commit: Text Adventure Game

Features:
- Combat system with AP/EP hit calculation and three-layer defense
- Auto-combat/farming mode
- Item system with stacking support
- Skill system with levels, milestones, and parent skill sync
- Shop system with dynamic pricing
- Inventory management with bulk selling
- Event system
- Game loop with offline earnings
- Save/Load system

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

components/common/Collapse.vue

@@ -0,0 +1,64 @@
+<template>
+  <view class="collapse">
+    <view class="collapse__header" @click="toggle">
+      <text class="collapse__title">{{ title }}</text>
+      <text class="collapse__arrow">{{ isExpanded ? '▼' : '▶' }}</text>
+    </view>
+    <view v-show="isExpanded" class="collapse__content">
+      <slot></slot>
+    </view>
+  </view>
+</template>
+
+<script setup>
+import { ref } from 'vue'
+
+const props = defineProps({
+  title: { type: String, default: '' },
+  expanded: { type: Boolean, default: false }
+})
+
+const emit = defineEmits(['toggle'])
+
+const isExpanded = ref(props.expanded)
+
+function toggle() {
+  isExpanded.value = !isExpanded.value
+  emit('toggle', isExpanded.value)
+}
+</script>
+
+<style lang="scss" scoped>
+.collapse {
+  border-top: 1rpx solid $border-color;
+
+  &__header {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    padding: 16rpx;
+    background-color: $bg-secondary;
+    cursor: pointer;
+
+    &:active {
+      background-color: $bg-tertiary;
+    }
+  }
+
+  &__title {
+    color: $text-primary;
+    font-size: 28rpx;
+  }
+
+  &__arrow {
+    color: $text-secondary;
+    font-size: 20rpx;
+    transition: transform 0.2s;
+  }
+
+  &__content {
+    padding: 16rpx;
+    background-color: $bg-primary;
+  }
+}
+</style>