feat: 套装方案对比与导出功能

- 新增套装方案对比页面(KitExport.vue)，支持4个套装(芳香调理/家庭医生/居家呵护/全精油)的配方匹配和成本对比
- 按各精油原瓶价占比分摊套装总价，计算每滴套装成本
- 支持设置配方售价，自动计算利润率
- Excel导出完整版(含成分明细)和简版，含横向对比sheet
- 抽取套装配置到共享config/kits.js，Inventory页复用
- 修复库存页模糊匹配bug(牛至错误匹配到牛至呵护)
- 修正全精油套装列表(补芫荽叶/加州胡椒/罗马洋甘菊/道格拉斯冷杉/西班牙鼠尾草，修正广藿香/斯里兰卡肉桂皮名称)
- 所有套装加入椰子油

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/composables/useKitCost.js

@@ -0,0 +1,136 @@
+import { computed } from 'vue'
+import { useOilsStore } from '../stores/oils'
+import { useRecipesStore } from '../stores/recipes'
+import { KITS } from '../config/kits'
+
+/**
+ * 套装成本分摊与配方匹配
+ *
+ * 分摊逻辑：按各精油原瓶价占比分摊套装总价
+ *   某精油套装内成本 = (该油原瓶价 / 套装内所有油原瓶价之和) × 套装总价
+ *   套装内每滴成本 = 套装内成本 / 该油滴数
+ */
+export function useKitCost() {
+  const oils = useOilsStore()
+  const recipeStore = useRecipesStore()
+
+  // Resolve kit oil name to system oil name (handles 牛至→西班牙牛至 etc.)
+  function resolveOilName(kitOilName) {
+    if (oils.oilsMeta[kitOilName]) return kitOilName
+    // Try finding system oil that ends with kit name
+    return oils.oilNames.find(n => n.endsWith(kitOilName) && n !== kitOilName) || kitOilName
+  }
+
+  // Calculate per-drop costs for a kit
+  function calcKitPerDrop(kit) {
+    const resolved = kit.oils.map(name => resolveOilName(name))
+    // Sum of bottle prices for all oils in kit
+    let totalBottlePrice = 0
+    const oilBottlePrices = {}
+    for (const name of resolved) {
+      const meta = oils.oilsMeta[name]
+      const bp = meta ? meta.bottlePrice : 0
+      oilBottlePrices[name] = bp
+      totalBottlePrice += bp
+    }
+    if (totalBottlePrice === 0) return {}
+
+    // Proportional allocation
+    const perDrop = {}
+    for (const name of resolved) {
+      const meta = oils.oilsMeta[name]
+      const bp = oilBottlePrices[name]
+      const kitCostForOil = (bp / totalBottlePrice) * kit.price
+      const drops = meta ? meta.dropCount : 1
+      perDrop[name] = drops > 0 ? kitCostForOil / drops : 0
+    }
+    return perDrop
+  }
+
+  // Check if a recipe can be made with a kit
+  function canMakeRecipe(kit, recipe) {
+    const resolvedSet = new Set(kit.oils.map(name => resolveOilName(name)))
+    return recipe.ingredients.every(ing => resolvedSet.has(ing.oil))
+  }
+
+  // Calculate recipe cost using kit pricing
+  function calcRecipeCostWithKit(kitPerDrop, recipe) {
+    return recipe.ingredients.reduce((sum, ing) => {
+      const ppd = kitPerDrop[ing.oil] || 0
+      return sum + ppd * ing.drops
+    }, 0)
+  }
+
+  // Get all matching recipes for a kit
+  function getKitRecipes(kit) {
+    const perDrop = calcKitPerDrop(kit)
+    return recipeStore.recipes
+      .filter(r => canMakeRecipe(kit, r))
+      .map(r => ({
+        ...r,
+        kitCost: calcRecipeCostWithKit(perDrop, r),
+        originalCost: oils.calcCost(r.ingredients),
+      }))
+      .sort((a, b) => a.name.localeCompare(b.name, 'zh'))
+  }
+
+  // Build full analysis for all kits
+  const kitAnalysis = computed(() => {
+    return KITS.map(kit => {
+      const perDrop = calcKitPerDrop(kit)
+      const recipes = getKitRecipes(kit)
+      return {
+        ...kit,
+        perDrop,
+        recipes,
+        recipeCount: recipes.length,
+      }
+    })
+  })
+
+  // Cross-kit comparison: all recipes that at least one kit can make
+  const crossComparison = computed(() => {
+    const analysis = kitAnalysis.value
+    const allRecipeIds = new Set()
+    for (const ka of analysis) {
+      for (const r of ka.recipes) allRecipeIds.add(r._id)
+    }
+
+    const rows = []
+    for (const id of allRecipeIds) {
+      // Find recipe info from any kit that has it
+      let recipe = null
+      const costs = {}
+      for (const ka of analysis) {
+        const found = ka.recipes.find(r => r._id === id)
+        if (found) {
+          if (!recipe) recipe = found
+          costs[ka.id] = found.kitCost
+        } else {
+          costs[ka.id] = null // kit can't make this recipe
+        }
+      }
+      rows.push({
+        id,
+        name: recipe.name,
+        tags: recipe.tags,
+        ingredients: recipe.ingredients,
+        originalCost: recipe.originalCost,
+        costs, // { aroma: 12.3, family: null, home3988: 10.8, full: 9.5 }
+      })
+    }
+    rows.sort((a, b) => a.name.localeCompare(b.name, 'zh'))
+    return rows
+  })
+
+  return {
+    KITS,
+    resolveOilName,
+    calcKitPerDrop,
+    canMakeRecipe,
+    calcRecipeCostWithKit,
+    getKitRecipes,
+    kitAnalysis,
+    crossComparison,
+  }
+}