fix etcpmon: stray brace in nat_type_to_string, add pipefail to build scripts

tools/etcpmon/build.bat

@@ -32,7 +32,7 @@ set "CURRENT_DIR=%CD%"
 
 REM Launch MSYS2 UCRT64 shell and run build script with real-time logging
 REM Using tee to show output in console AND save to log
-call "%MSYS2_PATH%\msys2_shell.cmd" -ucrt64 -here -defterm -no-start -c "cd tools/etcpmon && bash build.sh 2>&1 | tee build.log"
+call "%MSYS2_PATH%\msys2_shell.cmd" -ucrt64 -here -defterm -no-start -c "cd \"%CURRENT_DIR%/tools/etcpmon\" && bash build.sh 2>&1"
 
 set BUILD_RESULT=%ERRORLEVEL%
 

tools/etcpmon/build.sh

@@ -3,7 +3,7 @@
 # Usage: ./build.sh
 # Log is automatically saved to build.log
 
-set -e
+set -eo pipefail
 
 # Capture all output to log file
 LOG_FILE="build.log"

tools/etcpmon/etcpmon_gui.c

@@ -1220,7 +1220,6 @@ static const char* nat_type_to_string(uint8_t nat_type) {
         default:                      return "?";
     }
 }
-}
 
 void etcpmon_gui_update_socket_list(struct etcpmon_app* app,
                                      struct etcpmon_socket_info* list,