Give long replay bands stable request identities

runs/intervention-response-v2/prepare_pilot.py

@@ -114,18 +114,34 @@ def resolve_role_trace(base: dict[str, Any], role: str) -> Path:
     return trace
 
 
+def private_request_id(
+    *, source_sha256: str, line_number: int, original_id: str
+) -> str:
+    payload = f"{source_sha256}:{line_number}:{original_id}".encode()
+    return f"phase-v2-{hashlib.sha256(payload).hexdigest()}"
+
+
 def merge_role_traces(sources: tuple[Path, Path], target: Path) -> dict[str, Any]:
     target.parent.mkdir(parents=True, exist_ok=True)
     temporary = target.with_suffix(target.suffix + ".tmp")
     rows = 0
     with temporary.open("w", encoding="utf-8") as output:
         for source in sources:
+            source_digest = sha256_file(source)
             with source.open(encoding="utf-8") as input_file:
-                for line in input_file:
+                for line_number, line in enumerate(input_file, start=1):
                     if not line.strip():
                         continue
-                    json.loads(line)
-                    output.write(line if line.endswith("\n") else line + "\n")
+                    row = json.loads(line)
+                    original_id = str(
+                        row.get("request_id") or row.get("id") or line_number
+                    )
+                    row["request_id"] = private_request_id(
+                        source_sha256=source_digest,
+                        line_number=line_number,
+                        original_id=original_id,
+                    )
+                    output.write(json.dumps(row, ensure_ascii=False) + "\n")
                     rows += 1
     os.replace(temporary, target)
     return {
@@ -135,6 +151,7 @@ def merge_role_traces(sources: tuple[Path, Path], target: Path) -> dict[str, Any
         "rows": rows,
         "sources": [str(source) for source in sources],
         "source_sha256": [sha256_file(source) for source in sources],
+        "request_id_scheme": "sha256(source_sha256:line_number:original_id)",
     }