debug: properly set thread names on macOS

src/renderer/Thread.zig

@@ -198,6 +198,13 @@ pub fn threadMain(self: *Thread) void {
 fn threadMain_(self: *Thread) !void {
     defer log.debug("renderer thread exited", .{});
 
+    // Right now, on Darwin, `std.Thread.setName` can only name the current
+    // thread, and we have no way to get the current thread from within it,
+    // so instead we use this code to name the thread instead.
+    if (builtin.os.tag.isDarwin()) {
+        internal_os.macos.pthread_setname_np(&"renderer".*);
+    }
+
     // Setup our crash metadata
     crash.sentry.thread_state = .{
         .type = .renderer,