Update MSRV from 1.86 to 1.88 (#7579)

Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>

crates/emath/src/smart_aim.rs

@@ -113,7 +113,7 @@ fn simplest_digit_closed_range(min: i32, max: i32) -> i32 {
     if min <= 5 && 5 <= max {
         5
     } else {
-        (min + max) / 2
+        min.midpoint(max)
     }
 }