users: store timezone, default is "UTC"

crates/jwt/src/claims.rs

@@ -21,6 +21,7 @@ pub struct JwtClaims {
     pub email: Option<String>,
     pub is_admin: bool,
     pub roles: Vec<String>,
+    pub zoneinfo: String,
 }
 
 impl JwtClaims {
@@ -42,6 +43,7 @@ impl JwtClaims {
             email: user.email().map(String::from),
             is_admin: user.is_admin(),
             roles,
+            zoneinfo: user.timezone().into(),
         }
     }