feat(qc-gate): add QC-GATE real-time LOT status report as first pure Vue 3 + Vite page

Introduce QC-GATE station monitoring with stacked bar chart and filterable LOT table,
using Vue 3 SFC + ECharts via npm. Establishes the pure Vite page architecture pattern
(no Jinja2) for future page migration. Also removes stale design files and README.mdj.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

data/page_status.json

@@ -29,6 +29,13 @@
       "drawer_id": "reports",
       "order": 3
     },
+    {
+      "route": "/qc-gate",
+      "name": "QC-GATE 狀態",
+      "status": "released",
+      "drawer_id": "reports",
+      "order": 4
+    },
     {
       "route": "/tables",
       "name": "表格總覽",
@@ -113,4 +120,4 @@
       "admin_only": true
     }
   ]
-}
+}