add example of manual profiling

Author: armcknight

docs/platforms/apple/common/profiling/index.mdx

@@ -55,6 +55,31 @@ See the subsections below to learn about the various ways the profiler can be st
 
 By default, the profiler can only be started and stopped manually with calls to `SentrySDK.startProfiler` and `SentrySDK.stopProfiler`. All code that executes on all threads in between those calls will be recorded. The configurations shown above demonstrate configuring manual profiling mode.
 
+For example, if you wanted to profile everything that happens after starting a network request, and then updating a table view with the contents of the response, you could do is as follows (assuming you've already started the Sentry SDK with the options as shown above):
+
+```swift {tabTitle:Swift}
+import Sentry
+
+struct MyModel: Codable {
+    // fields...
+}
+var model: MyModel?
+var tableView: UITableView!
+
+@IBAction func updateTable() {
+    SentrySDK.startProfiler()
+    URLSession.shared.dataTask(with: URLRequest(url: URL(string: "https://my.domain.tld/endpoint")!)) { data, response, error in
+        self.model = try! JSONDecoder().decode(MyModel.self, from: data!)
+        DispatchQueue.main.async {
+            self.tableView.reloadData()
+            SentrySDK.stopProfiler()
+        }
+    }
+}
+```
+
+This would capture every stacktrace on every thread involved with performing the network request, decoding the response and rebuilding the cells in the table view.
+
 ### Trace Lifecycle
 
 The profiler can be configured to start when a new root span is started where none already exist, and stopped when there are no root spans remaining. For this mode, you must set the `SentryProfileOptions.lifecycle` property to `SentryProfileLifecycleTrace` and ensure some traces will be sampled: