fix(rust/clippy): use RangeInclusive::contains and HashMap::keys

CI runs cargo clippy with -D warnings. The yesterday's HRDPS commits
introduced two pedantic-but-blocked lints:

- grid.rs:97 in_conus_bbox used `>=`/`<=` chain — clippy's
  manual_range_contains says use (LAT_MIN..=LAT_MAX).contains(&lat).
- pipeline.rs:426 backfill_dpt_from_depr iterated `cell.iter()` and
  threw the values away — clippy's iter_kv_map says use
  cell.keys().filter_map(...). Tightened the inline format strings
  to `{depr_key}` instead of the deprecated `{}`-with-arg form to
  avoid a follow-up useless_format complaint on the same touch.

cargo clippy --all-targets -- -D warnings passes; cargo test
--release stays at 158 passed.

rust/prop_grid_rs/src/grid.rs

@@ -94,7 +94,7 @@ pub fn hrdps_only_points() -> Vec<(f64, f64)> {
 
 #[inline]
 fn in_conus_bbox(lat: f64, lon: f64) -> bool {
-    lat >= LAT_MIN && lat <= LAT_MAX && lon >= LON_MIN && lon <= LON_MAX
+    (LAT_MIN..=LAT_MAX).contains(&lat) && (LON_MIN..=LON_MAX).contains(&lon)
 }
 
 /// Matches Elixir's `Float.round(x, 3)` — banker's rounding isn't used,

rust/prop_grid_rs/src/pipeline.rs

@@ -424,16 +424,15 @@ fn backfill_dpt_from_depr(cell: &mut CellValues) {
     // two passes so the iteration in pass 1 isn't invalidated by the
     // mutation in pass 2.
     let pending: Vec<(std::sync::Arc<str>, f32)> = cell
-        .iter()
-        .filter_map(|(key, _)| {
+        .keys()
+        .filter_map(|key| {
             let depr_key = key.strip_prefix("DEPR:")?;
-            let tmp_key = format!("TMP:{}", depr_key);
-            let dpt_key: std::sync::Arc<str> = format!("DPT:{}", depr_key).into();
+            let tmp_key: std::sync::Arc<str> = format!("TMP:{depr_key}").into();
+            let dpt_key: std::sync::Arc<str> = format!("DPT:{depr_key}").into();
             if cell.contains_key(&dpt_key) {
                 return None;
             }
-            let tmp_lookup: std::sync::Arc<str> = tmp_key.into();
-            let tmp = cell.get(&tmp_lookup).copied()?;
+            let tmp = cell.get(&tmp_key).copied()?;
             let depr = cell.get(key).copied()?;
             Some((dpt_key, tmp - depr))
         })