Turbopack Tracing: show memory consumption (vercel/turborepo#8020)

### Description

show allocated memory while loading to allow finding peek memory.

### Testing Instructions

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  Give a quick description of steps to test your changes.
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Closes PACK-2989

crates/turbopack-trace-server/src/reader/heaptrack.rs

@@ -102,6 +102,8 @@ pub struct HeaptrackFormat {
     collapse_crates: HashSet<String>,
     expand_crates: HashSet<String>,
     expand_recursion: bool,
+    allocated_memory: u64,
+    temp_allocated_memory: u64,
 }
 
 const RECURSION_IP: usize = 1;
@@ -153,19 +155,24 @@ impl HeaptrackFormat {
                 .map(|s| s.to_string())
                 .collect(),
             expand_recursion: env::var("EXPAND_RECURSION").is_ok(),
+            allocated_memory: 0,
+            temp_allocated_memory: 0,
         }
     }
 }
 
 impl TraceFormat for HeaptrackFormat {
     fn stats(&self) -> String {
         format!(
-            "{} spans, {} strings, {} ips, {} traces, {} allocations",
+            "{} spans, {} strings, {} ips, {} traces, {} allocations, {:.2} GB allocated, {:.2} \
+             GB temporarily allocated",
             self.spans,
             self.strings.len() - 1,
             self.trace_instruction_pointers.len() - 1,
             self.traces.len() - 1,
-            self.allocations.len() - 1
+            self.allocations.len() - 1,
+            (self.allocated_memory / 1024 / 1024) as f32 / 1024.0,
+            (self.temp_allocated_memory / 1024 / 1024) as f32 / 1024.0,
         )
     }
 
@@ -419,6 +426,7 @@ impl TraceFormat for HeaptrackFormat {
                         let TraceData { span_index, .. } =
                             self.traces.get(*trace_index).context("trace not found")?;
                         store.add_allocation(*span_index, *size, 1, &mut outdated_spans);
+                        self.allocated_memory += *size;
                     }
                 }
                 b'-' => {
@@ -432,6 +440,8 @@ impl TraceFormat for HeaptrackFormat {
                         let TraceData { span_index, .. } =
                             self.traces.get(*trace_index).context("trace not found")?;
                         store.add_deallocation(*span_index, *size, 1, &mut outdated_spans);
+                        self.allocated_memory -= *size;
+                        self.temp_allocated_memory += *size;
                     }
                 }
                 b'R' => {