feat: add benchmark-programs — 58 telecom COBOL test programs

作为子目录纳入系统，与核心测试管道协同

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

benchmark-programs/32-mix-1N-samekeybreak/README.md

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+# 32-mix-1N-samekeybreak — 1:N Matching with Same-Key Break
+
+## 电信业务场景
+
+合同+月别混合集计。先做合同↔CDR的1:N匹配，再在匹配结果内做同键(key)的月别集计。同时演示匹配和key切两种模式。
+
+## Purpose
+Demonstrates 1:N matching pattern (one master to many details) combined with same-key break summarization.
+
+## Test Coverage
+1. **1:N matching** — One master (KEY0000001) matched to three detail records
+2. **Same-key break** — When detail key changes, a summary line is output with count and total
+3. **Multiple master matches** — Records for KEY0000001, KEY0000002, KEY0000004
+4. **Unmatched detail** — Master lookup not found (if key is missing)
+5. **Final break** — Last group summary at end of file
+
+## Data
+- 5 master records (KEY0000001 through KEY0000005)
+- 8 detail records with keys repeating for 1:N matching
+
+## Key Techniques
+- In-memory master table loaded from file
+- Sequential file matching
+- Key break detection on key field change
+- Accumulator reset at each break
+- Grand total across all matches