feat(coderd): set full name from IDP name claim (#13468)

* Updates OIDC and GitHub OAuth login to fetch set name from relevant claim fields
* Adds CODER_OIDC_NAME_FIELD as configurable source of user name claim
* Adds httpapi function to normalize a username such that it will pass validation
* Adds firstName / lastName fields to dev OIDC setup

coderd/httpapi/name.go

@@ -91,3 +91,14 @@ func UserRealNameValid(str string) error {
 	}
 	return nil
 }
+
+// NormalizeUserRealName normalizes a user name such that it will pass
+// validation by UserRealNameValid. This is done to avoid blocking
+// little  Bobby  Whitespace  from using Coder.
+func NormalizeRealUsername(str string) string {
+	s := strings.TrimSpace(str)
+	if len(s) > 128 {
+		s = s[:128]
+	}
+	return s
+}