- Add _compute_modes() to derive OutputStyle, has_const, dest_count from edge topology - Add _compute_frame_layouts() for frame slot assignment per activation - Add _assign_act_ids() replacing _assign_context_slots() for 3-bit activation IDs - Remove _assign_context_slots() function - Update allocate() main flow to call new functions in sequence - Add comprehensive test suite in tests/test_allocate_frames.py Verifies AC5.2 (canonical layouts), AC5.3 (sequential activation IDs), AC5.4 (slot assignment order), AC5.5 (mode computation), AC5.6 (overflow checking), AC5.7 (exhaustion detection)