[PROF-8967] Reduce memory footprint and allocations for profiling timeline data

profiling/Cargo.toml

@@ -42,4 +42,5 @@ serde = {version = "1.0", features = ["derive"]}
 serde_json = {version = "1.0"}
 tokio = {version = "1.23", features = ["rt", "macros"]}
 tokio-util = "0.7.1"
+byteorder = { version = "1.5", features = ["std"] }
 uuid = { version = "1.4.1", features = ["v4", "serde"] }

profiling/src/internal/label.rs

@@ -150,3 +150,9 @@ impl LabelSetId {
         self.0 as usize
     }
 }
+
+impl From<LabelSetId> for u32 {
+    fn from(value: LabelSetId) -> Self {
+        value.0
+    }
+}

profiling/src/internal/observation/mod.rs

@@ -9,6 +9,7 @@
 //! single pointer of overhead.
 
 mod observations;
+mod timestamped_observations;
 mod trimmed_observation;
 
 // We keep trimmed_observation private, to ensure that only maps can make and