refactor(log): remove deprecated utility/log.h

- Remove src/libipc/utility/log.h as it's no longer used
- All code has been migrated to use the new libipc/imp/log.h interface
- The old utility/log.h provided printf-style logging: ipc::log() and ipc::error()
- The new imp/log.h provides modern C++ stream-based logging with LIBIPC_LOG() macro
- Verified that there are no remaining references to utility/log.h in the codebase

This completes the log interface migration by removing the deprecated file.

src/libipc/utility/log.h

@@ -1,39 +0,0 @@
-#pragma once
-
-#include <cstdio>
-#include <utility>
-
-namespace ipc {
-namespace detail {
-
-template <typename O>
-void print(O out, char const * str) {
-    std::fprintf(out, "%s", str);
-}
-
-template <typename O, typename P1, typename... P>
-void print(O out, char const * fmt, P1&& p1, P&&... params) {
-    std::fprintf(out, fmt, std::forward<P1>(p1), std::forward<P>(params)...);
-}
-
-} // namespace detail
-
-inline void log(char const * fmt) {
-    ipc::detail::print(stdout, fmt);
-}
-
-template <typename P1, typename... P>
-void log(char const * fmt, P1&& p1, P&&... params) {
-    ipc::detail::print(stdout, fmt, std::forward<P1>(p1), std::forward<P>(params)...);
-}
-
-inline void error(char const * str) {
-    ipc::detail::print(stderr, str);
-}
-
-template <typename P1, typename... P>
-void error(char const * fmt, P1&& p1, P&&... params) {
-    ipc::detail::print(stderr, fmt, std::forward<P1>(p1), std::forward<P>(params)...);
-}
-
-} // namespace ipc