Move buildLuaDispatch and isLuaProtocol from private to
protected/public so IPCTestHelper can access them.
Add 7 tests covering all buildLuaDispatch branches, dispatch
error path, and isLuaProtocol cache behavior.
Hyprland 0.54 replaced the text-based dispatch socket protocol with a
Lua-based one. Commands like "dispatch workspace 1" are now interpreted
as invalid Lua (return hl.dispatch(workspace 1)), breaking workspace
clicks and scroll navigation.
Add IPC::dispatch() that probes the running Hyprland on first call and
routes commands through the new hl.dsp Lua API when the Lua protocol is
detected, falling back to the old text format otherwise.