硬性策略质量门禁 validate_strategy()

新增 STRATEGY_QUALITY_GATES 检查清单（9条红线）：
CRITICAL: 止损/止盈存在+>0, 买入区下沿<上沿
HIGH: 止损≤买入区, 买入推荐含RR≥1.5, 港股标currency=HKD
MEDIUM: signal短词, tech_snapshot含技术位

enforce_strategy_quality() 插在写入链的两处：
1. reassess_with_context() return前 → 单只重评必过
2. regenerate_all() for d in decisions: 写DB前 → 批量重评必过

不过的：status=review_needed, signal降级→信号不充分
不会写进DB/JSON，除非修复了CRITICAL问题

data/stocks/06869.json

@@ -21,6 +21,11 @@
       "content": "长飞光纤光缆(06869) 255.40+6.68%放量大涨，持有等站上成本263.72；腾讯(00700) 429.80+2.28%，买入区435-440依然可加；中芯H(00981) 89.40+",
       "report_id": "cron_99c06255590a_2026-07-01_08-39-42"
     },
+    {
+      "time": "2026-07-02T08:55:30.266659",
+      "content": "- **长飞光纤(06869)** 255.4 / 止损205.71 — 浮亏-3%，光通信受半导拖累，250不破则持",
+      "report_id": "cron_99c06255590a_2026-07-02_08-32-48"
+    },
     {
       "time": "2026-06-02T13:56:05.495125",
       "content": "🔺**长飞光纤(06869)** | 231.00 +9.90% | 买入区210~220已超出，等回调再入3%",