server: add not_modified check when no 'to' param

crates/brk_core/src/structs/timestamp.rs

@@ -1,10 +1,7 @@
 use std::ops::{Add, Div};
 
 use derive_deref::Deref;
-use jiff::{
-    civil::{Time, date},
-    tz::TimeZone,
-};
+use jiff::{civil::date, tz::TimeZone};
 use serde::Serialize;
 use zerocopy::{FromBytes, Immutable, IntoBytes, KnownLayout};