feat(users): apply django password validators in auth flows

core/validators/password.py

@@ -0,0 +1,29 @@
+import re
+
+from django.core.exceptions import ValidationError
+
+
+class PasswordComplexityValidator:
+    lower_pattern = re.compile(r"[a-z]")
+    upper_pattern = re.compile(r"[A-Z]")
+    digit_pattern = re.compile(r"\d")
+    symbol_pattern = re.compile(r"[^A-Za-z0-9]")
+
+    message = (
+        "Password must be at least 8 characters and include at least one lowercase "
+        "letter, one uppercase letter, one digit, and one symbol."
+    )
+    code = "password_no_complexity"
+
+    def validate(self, password, user=None):
+        if (
+            len(password) < 8
+            or not self.lower_pattern.search(password)
+            or not self.upper_pattern.search(password)
+            or not self.digit_pattern.search(password)
+            or not self.symbol_pattern.search(password)
+        ):
+            raise ValidationError(self.message, code=self.code)
+
+    def get_help_text(self):
+        return self.message