fix(cert): 去掉变频器频率/电导率/延伸率/辊缝图表，折线改直线

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/views/Production.vue

@@ -332,8 +332,10 @@ export default {
     certCharts() {
       const pd = this.certRow && this.certRow.process_data
       if (!pd || !Array.isArray(pd.items) || !pd.items.length) return []
+      const EXCLUDE = /变频器频率|电导率|延伸率|辊缝/
       const groups = {}
       pd.items.forEach(it => {
+        if (EXCLUDE.test(it.label || '')) return
         const v = parseFloat(it.value)
         if (isNaN(v)) return
         const u = it.unit || '其他'
@@ -349,7 +351,7 @@ export default {
           series = { type: 'bar', data, itemStyle: { color, borderRadius: [3, 3, 0, 0] }, barMaxWidth: 18 }
         } else {
           series = {
-            type: 'line', data, smooth: true, symbol: 'circle', symbolSize: 6,
+            type: 'line', data, smooth: false, symbol: 'circle', symbolSize: 6,
             itemStyle: { color }, lineStyle: { color, width: 2 },
             areaStyle: kind === 'area' ? { color, opacity: 0.12 } : undefined,
           }