optimize memory issues (#767)

* optimize memory issues

1. introduce jemalloc support, which can dump current memory usage
2. reduce the GlobalEvent broadcaster memory usage.
3. reduce tcp & udp tunnel memory usage

TODO: if peer conn tunnel hangs, the unbounded channel of peer rpc
may consume lots of memory, which should be improved.

* select a port from 15888+ when port is 0

Cargo.toml

@@ -1,6 +1,11 @@
 [workspace]
 resolver = "2"
-members = ["easytier", "easytier-gui/src-tauri", "easytier-rpc-build", "easytier-web"]
+members = [
+    "easytier",
+    "easytier-gui/src-tauri",
+    "easytier-rpc-build",
+    "easytier-web",
+]
 default-members = ["easytier", "easytier-web"]
 
 [profile.dev]