Add CallerIdentity dataclass and batch JSON parser

backend/services/caller_gen.py

@@ -0,0 +1,38 @@
+from dataclasses import dataclass
+from typing import Optional
+import json
+
+REQUIRED_FIELDS = {
+    "name", "age", "voice_suggestion", "location", "identity",
+    "situation", "reason_calling", "opening_line", "secret_want",
+    "specific_details", "emotional_register"
+}
+
+
+@dataclass
+class CallerIdentity:
+    name: str
+    age: int
+    voice_suggestion: str
+    location: str
+    identity: str
+    situation: str
+    reason_calling: str
+    opening_line: str
+    secret_want: str
+    specific_details: list[str]
+    emotional_register: str
+    # set after voice validation
+    voice_resolved: Optional[str] = None
+
+
+def parse_batch_response(raw: str) -> list[CallerIdentity]:
+    data = json.loads(raw)
+    callers = data.get("callers", [])
+    result = []
+    for c in callers:
+        missing = REQUIRED_FIELDS - set(c.keys())
+        if missing:
+            raise ValueError(f"CallerIdentity missing fields: {missing}")
+        result.append(CallerIdentity(**{k: c[k] for k in REQUIRED_FIELDS}))
+    return result