fix: don't starve high priority requests (#2660)

crates/interfaces/src/p2p/priority.rs

@@ -8,3 +8,15 @@ pub enum Priority {
     /// Queued from the front for download requests.
     High,
 }
+
+impl Priority {
+    /// Returns `true` if this is [Priority::High]
+    pub fn is_high(&self) -> bool {
+        matches!(self, Priority::High)
+    }
+
+    /// Returns `true` if this is [Priority::Normal]
+    pub fn is_normal(&self) -> bool {
+        matches!(self, Priority::Normal)
+    }
+}