Make the memory reporting multi-process aware (#35863)

So far the memory reporter aggregates reports from all processes, and
runs the system reporter only in the main process. Instead it is
desirable to have per-process reports. We do so by:
- creating a ProcessReports struct that holds includes the pid in
addition to the reports themselves.
- running the system memory reporter also in content processes.
- updating the about:memory page to create one report per process, and
add useful information like the pid and the urls loaded in a given
process.

<!-- Please describe your changes on the following line: -->


---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors


![image](https://github.com/user-attachments/assets/0bafe140-539d-4d6a-8316-639309a22d4a)

Signed-off-by: webbeef <me@webbeef.org>

components/script/dom/workerglobalscope.rs

@@ -24,6 +24,7 @@ use net_traits::request::{
     CredentialsMode, Destination, InsecureRequestsPolicy, ParserMetadata,
     RequestBuilder as NetRequestInit,
 };
+use profile_traits::mem::ProcessReports;
 use script_traits::WorkerGlobalScopeInit;
 use servo_url::{MutableOrigin, ServoUrl};
 use timers::TimerScheduler;
@@ -535,7 +536,7 @@ impl WorkerGlobalScope {
             CommonScriptMsg::CollectReports(reports_chan) => {
                 let cx = self.get_cx();
                 let reports = cx.get_reports(format!("url({})", self.get_url()));
-                reports_chan.send(reports);
+                reports_chan.send(ProcessReports::new(reports));
             },
         }
         true