Phase 3 (L8). Pure statement-for-statement relocation into
dsp/ratio_seq.hpp, dsp/seq_clock.hpp and core/event_queue.hpp.
AUDIT CORRECTION: L8 says "breakor and elysiamorf duplicate ratio_seq". That is
false — ElysiamorfEngine has no ratio_seq at all; it triggers continuously via
FM operators. The real duplicate pair is BreakOrEngine and MEMLCeliumEngine,
whose copies are byte-for-byte identical. Elysiamorf did share the clock and
event-queue machinery, so it uses those. memlcelium now includes the shared
ratio_seq too, which is what actually closes this finding.
Deliberately NOT folded into core/ring_buffer.hpp: RingBuffer is an
atomics-based cross-core SPSC channel (its header says so), whereas the engines'
event queue is produced and drained on one thread. Reusing it would have meant
paying for atomics to serve a single-threaded FIFO. The distinction is now
recorded in MAP.md so the next audit does not read them as duplicates.
Bit-exactness: verified the MIDI-clock tick and bar-phasor tick preserve the
original operation order with no floating-point re-association, and that
EventQueue keeps the original `% N` indexing rather than adopting RingBuffer's
bitmask. The golden suite (nisps_golden_tests) and the native<->WASM parity blob
both pass unchanged — they are the check, and they were not re-baselined.
