fix: 下架改用原生fetch调试、翻译保存错误可见、手机字号加大

下架:
- 改用原生 fetch 替代 api.post，避免抽象层干扰
- 详细错误信息: status code + response text
- 分步检查: name/meta 为空时分别提示

翻译保存:
- 失败不再静默吞掉，显示成功/失败数量
- console.error 记录具体失败原因

手机字号:
- @media(max-width:480px): 名称13px 英文9px 价格12px
- grid 最小宽度160px，间距8px

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

frontend/src/components/RecipeDetailOverlay.vue

@@ -624,17 +624,24 @@ async function applyTranslation() {
   }
 
   // 2. Save each oil's English name to oils table (syncs with oil reference page)
+  let failed = 0
   for (const [oilName, enName] of Object.entries(customOilNameEn.value)) {
     if (!enName?.trim()) continue
     const meta = oilsStore.oilsMeta[oilName]
-    if (!meta || meta.enName === enName.trim()) continue
+    if (!meta) continue
+    if (meta.enName === enName.trim()) continue
     try {
       await oilsStore.saveOil(oilName, meta.bottlePrice, meta.dropCount, meta.retailPrice, enName.trim())
       saved++
-    } catch {}
+    } catch (e) {
+      console.error('Save oil en_name failed:', oilName, e)
+      failed++
+    }
   }
 
-  if (saved > 0) ui.showToast(`翻译已保存（${saved}项）`)
+  if (saved > 0) ui.showToast(`翻译已保存（${saved}项）` + (failed > 0 ? `，${failed}项失败` : ''))
+  else if (failed > 0) ui.showToast(`保存失败 ${failed} 项`)
+  else ui.showToast('没有修改')
 
   cardImageUrl.value = null
   nextTick(() => generateCardImage())