feat: 配方卡片容量切换、预览/保存流程优化、精油搜索自动补全、精油英文名编辑

1. 配方卡片视图加回容量切换按钮（单次/2.5ml/5ml…），
   非单次容量的滴数通过 Math.round 取整显示
2. 编辑器「预览」按钮改为展示当前未保存数据；
   预览后点关闭询问是否保存；
   直接点「保存」后留在配方卡片视图（不再关闭弹层）
3. 添加精油改为搜索输入框 + 下拉自动补全，
   支持中文名和英文名筛选
4. 精油价目：添加/编辑表单加入英文名字段；
   编辑/删除按钮改为悬停（桌面）或点击（移动端）才显示；
   后端及数据库同步支持 oils.en_name

backend/database.py

@@ -221,6 +221,8 @@ def init_db():
         c.execute("ALTER TABLE oils ADD COLUMN retail_price REAL")
     if "is_active" not in oil_cols:
         c.execute("ALTER TABLE oils ADD COLUMN is_active INTEGER DEFAULT 1")
+    if "en_name" not in oil_cols:
+        c.execute("ALTER TABLE oils ADD COLUMN en_name TEXT DEFAULT ''")
 
     # Migration: add new columns to category_modules if missing
     cat_cols = [row[1] for row in c.execute("PRAGMA table_info(category_modules)").fetchall()]

backend/main.py

@@ -79,6 +79,7 @@ class OilIn(BaseModel):
     bottle_price: float
     drop_count: int
     retail_price: Optional[float] = None
+    en_name: Optional[str] = None
 
 
 class IngredientIn(BaseModel):
@@ -649,7 +650,7 @@ def impersonate(body: dict, user=Depends(require_role("admin"))):
 @app.get("/api/oils")
 def list_oils():
     conn = get_db()
-    rows = conn.execute("SELECT name, bottle_price, drop_count, retail_price, is_active FROM oils ORDER BY name").fetchall()
+    rows = conn.execute("SELECT name, bottle_price, drop_count, retail_price, is_active, en_name FROM oils ORDER BY name").fetchall()
     conn.close()
     return [dict(r) for r in rows]
 
@@ -658,9 +659,10 @@ def list_oils():
 def upsert_oil(oil: OilIn, user=Depends(require_role("admin", "senior_editor"))):
     conn = get_db()
     conn.execute(
-        "INSERT INTO oils (name, bottle_price, drop_count, retail_price) VALUES (?, ?, ?, ?) "
-        "ON CONFLICT(name) DO UPDATE SET bottle_price=excluded.bottle_price, drop_count=excluded.drop_count, retail_price=excluded.retail_price",
-        (oil.name, oil.bottle_price, oil.drop_count, oil.retail_price),
+        "INSERT INTO oils (name, bottle_price, drop_count, retail_price, en_name) VALUES (?, ?, ?, ?, ?) "
+        "ON CONFLICT(name) DO UPDATE SET bottle_price=excluded.bottle_price, drop_count=excluded.drop_count, "
+        "retail_price=excluded.retail_price, en_name=COALESCE(excluded.en_name, oils.en_name)",
+        (oil.name, oil.bottle_price, oil.drop_count, oil.retail_price, oil.en_name),
     )
     log_audit(conn, user["id"], "upsert_oil", "oil", oil.name, oil.name,
               json.dumps({"bottle_price": oil.bottle_price, "drop_count": oil.drop_count}))