Implement operator login service and fix static root

Data/Engine/builders/operator_auth.py

@@ -0,0 +1,72 @@
+"""Builders for operator authentication payloads."""
+
+from __future__ import annotations
+
+import hashlib
+from dataclasses import dataclass
+from typing import Mapping
+
+
+@dataclass(frozen=True, slots=True)
+class OperatorLoginRequest:
+    """Normalized operator login credentials."""
+
+    username: str
+    password_sha512: str
+
+
+@dataclass(frozen=True, slots=True)
+class OperatorMFAVerificationRequest:
+    """Normalized MFA verification payload."""
+
+    pending_token: str
+    code: str
+
+
+def _sha512_hex(raw: str) -> str:
+    digest = hashlib.sha512()
+    digest.update(raw.encode("utf-8"))
+    return digest.hexdigest()
+
+
+def build_login_request(payload: Mapping[str, object]) -> OperatorLoginRequest:
+    """Validate and normalize the login *payload*."""
+
+    username = str(payload.get("username") or "").strip()
+    password_sha512 = str(payload.get("password_sha512") or "").strip().lower()
+    password = payload.get("password")
+
+    if not username:
+        raise ValueError("username is required")
+
+    if password_sha512:
+        normalized_hash = password_sha512
+    else:
+        if not isinstance(password, str) or not password:
+            raise ValueError("password is required")
+        normalized_hash = _sha512_hex(password)
+
+    return OperatorLoginRequest(username=username, password_sha512=normalized_hash)
+
+
+def build_mfa_request(payload: Mapping[str, object]) -> OperatorMFAVerificationRequest:
+    """Validate and normalize the MFA verification *payload*."""
+
+    pending_token = str(payload.get("pending_token") or "").strip()
+    raw_code = str(payload.get("code") or "").strip()
+    digits = "".join(ch for ch in raw_code if ch.isdigit())
+
+    if not pending_token:
+        raise ValueError("pending_token is required")
+    if len(digits) < 6:
+        raise ValueError("code must contain 6 digits")
+
+    return OperatorMFAVerificationRequest(pending_token=pending_token, code=digits)
+
+
+__all__ = [
+    "OperatorLoginRequest",
+    "OperatorMFAVerificationRequest",
+    "build_login_request",
+    "build_mfa_request",
+]