refactor(tests): replace libexpect with forkpty() for PTY handling

- Remove dependency on libexpect/tcl
- Implement native PTY handling with forkpty()
- Add prof_output_exact/regex for flexible output matching
- Improve timeout handling and synchronization

tests/functionaltests/proftest.h

@@ -4,6 +4,8 @@
 #define XDG_CONFIG_HOME "./tests/functionaltests/files/xdg_config_home"
 #define XDG_DATA_HOME   "./tests/functionaltests/files/xdg_data_home"
 
+extern int stub_port;
+
 int init_prof_test(void **state);
 int close_prof_test(void **state);