feat: 新增产品表单(ml/g/颗)+配方卡片显示产品容量

- 精油价目新增分两个tab：新增精油(标准容量) / 新增其他产品(ml/g/颗)
- saveOil支持unit参数
- 配方卡片：含产品的配方直接显示产品用量+单位(如30g)

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

frontend/src/components/RecipeCard.vue

@@ -56,13 +56,10 @@ const volumeLabel = computed(() => {
     if (ml <= 2) return '单次'
     return `${Math.round(ml)}ml`
   }
-  // Non-coconut: check if has portion product, extract volume from note
-  const hasPortion = ings.some(i => oilsStore.isPortionUnit(i.oil))
-  if (hasPortion) {
-    const note = props.recipe.note || ''
-    const m = note.match(/(\d+)\s*(ml|毫升|克|g)/i)
-    if (m) return `${m[1]}${m[2].toLowerCase()}`
-    return '调配'
+  // Non-coconut: find portion product and show its amount + unit
+  const portionIng = ings.find(i => oilsStore.isPortionUnit(i.oil))
+  if (portionIng) {
+    return `${portionIng.drops}${oilsStore.unitLabel(portionIng.oil)}`
   }
   return ''
 })