feat: 真实数据时间对齐集成测试框架

- tests/realdata_contract.py：数据契约底座（SRT 解析/清洗、时间对齐量化
  指标 align_report、幻觉词/专名判定、提示词规则拼接）
- tests/test_integration_alignment.py：流水线产物 vs 硬字幕参考的时间对齐
  （真实数据复现"字幕过早/过晚"，红→绿闭环）
- tests/test_integration_prompt_rules.py：寒暄幻觉/专名提示词规则测试
- scripts/extract_reference_srt.py：从烧录字幕视频自动提取参考时间轴
- testdata/REALDATA_README.md + alignment/*.reference.srt：真实参考字幕
  （视频素材较大，gitignore 不入库）

testdata/alignment/ATID-642_2min.reference.srt

@@ -0,0 +1,103 @@
+7
+00:00:17,766 --> 00:00:21,828
+辛苦了 上午的检查已经OK了
+
+16
+00:00:31,980 --> 00:00:34,011
+谢谢你 松井小姐
+
+17
+00:00:34,010 --> 00:00:37,564
+还有没有什么困扰 或者奇怪的地方吗
+
+18
+00:00:38,071 --> 00:00:39,594
+没问题啦
+
+19
+00:00:39,594 --> 00:00:42,640
+总感觉果林前辈每次都会问这个呢
+
+20
+00:00:42,640 --> 00:00:43,148
+总感觉果林前辈 每次都会问这个呢
+
+21
+00:00:43,147 --> 00:00:46,193
+是呢 抱歉
+
+22
+00:00:48,223 --> 00:00:49,239
+V
+
+23
+00:00:49,239 --> 00:00:51,777
+那么 松井小姐
+
+24
+00:00:51,777 --> 00:00:52,792
+V
+
+25
+00:00:52,792 --> 00:00:55,838
+你来我们医院也才一个月吧
+
+26
+00:00:56,345 --> 00:00:59,391
+记得挺快嘛 没有啦
+
+27
+00:01:00,914 --> 00:01:04,467
+因为果林前辈教得好呀
+
+28
+00:01:04,467 --> 00:01:08,527
+因为 你和患者们 也已经完全打成一片了
+
+29
+00:01:09,036 --> 00:01:11,574
+我是北冈果林
+
+30
+00:01:11,574 --> 00:01:16,143
+在这家综合医院工作的护士
+
+31
+00:01:16,650 --> 00:01:19,188
+她叫松井日奈子
+
+32
+00:01:19,188 --> 00:01:24,264
+是一个月前开始 在这间医院工作的新人护士
+
+33
+00:01:25,279 --> 00:01:28,324
+上吧 上吧
+
+34
+00:01:28,832 --> 00:01:33,908
+不行 受不了 好了 上吧
+
+35
+00:01:37,462 --> 00:01:40,000
+状态不错
+
+36
+00:01:40,000 --> 00:01:42,538
+请进
+
+37
+00:01:47,107 --> 00:01:49,645
+早安
+
+38
+00:01:50,660 --> 00:01:52,183
+金山先生
+
+39
+00:01:52,183 --> 00:01:57,259
+昨晚你住院时我不在没能照顾到你非常抱歉
+
+40
+00:01:57,259 --> 00:02:00,304
+我是医务室长权藤 请多关照

testdata/alignment/sample.reference.srt

@@ -0,0 +1,19 @@
+1
+00:00:00,000 --> 00:00:01,440
+---
+
+2
+00:00:01,440 --> 00:00:04,320
+SUB 001
+
+3
+00:00:05,760 --> 00:00:06,240
+---
+
+4
+00:00:06,240 --> 00:00:09,120
+SUB 002
+
+5
+00:00:09,600 --> 00:00:10,080
+---