fix memory leak in Waker move assignment (#42)

* fix memory leak in Waker move assignment

* add a debug codesign for MacOS Instruments

examples/echo_server/debug.plist

@@ -0,0 +1 @@
+<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "https://www.apple.com/DTDs/PropertyList-1.0.dtd"><plist version="1.0"><dict><key>com.apple.security.get-task-allow</key><true/></dict></plist>

examples/echo_server/justfile

@@ -11,6 +11,7 @@ build:
                    -DCMAKE_TOOLCHAIN_FILE=toolchain.cmake \
                    -DCMAKE_INTERPROCEDURAL_OPTIMIZATION=ON
     cmake --build build --parallel 4 --config Release --verbose
+    codesign -s - -v -f --entitlements debug.plist ./build/echo_server
 
 run:
     SOCKET_LOG=info ./build/echo_server

socket_manager/waker.cc

@@ -13,6 +13,9 @@ namespace socket_manager {
   }
 
   Waker &Waker::operator=(Waker &&other) noexcept {
+    if (waker.Data != nullptr && waker.Vtable != nullptr) {
+      socket_manager_waker_free(waker);
+    }
     waker = other.waker;
     other.waker.Data = nullptr;
     other.waker.Vtable = nullptr;