Prepare ERP source for Gitea deployment

app/core/security/otp.py

@@ -0,0 +1,23 @@
+import secrets
+from fastapi import Request
+
+OTP_CODE_KEY = "otp_code"
+OTP_VERIFIED_KEY = "otp_verified"
+
+def start_otp(request: Request) -> str:
+    # 6-digit numeric code
+    code = str(secrets.randbelow(900000) + 100000)
+    request.session[OTP_CODE_KEY] = code
+    request.session[OTP_VERIFIED_KEY] = False
+    return code
+
+def verify_otp(request: Request, code: str) -> bool:
+    expected = request.session.get(OTP_CODE_KEY)
+    if expected and code and code.strip() == expected:
+        request.session[OTP_VERIFIED_KEY] = True
+        request.session.pop(OTP_CODE_KEY, None)
+        return True
+    return False
+
+def is_otp_verified(request: Request) -> bool:
+    return bool(request.session.get(OTP_VERIFIED_KEY))