v1.9.0 "Marionette"

Fifth release of the RustyNES-parity roadmap: Lua scripting bus-widening.

Added

• Lua scripting: full-bus reads — rustysnes-script's emu.read(addr) now reaches
  [Bus::peek] (the full 24-bit bus: WRAM, cart ROM/SRAM; I/O register space still reads back as
  0, Bus::peek's own documented behavior, matching the debugger's Memory panel), widened from
  [Bus::peek_wram] (WRAM-only). emu.write(addr, val) stays scoped to
  [Bus::poke_wram] (WRAM only) — a side-effect-free "poke" has no clean semantic for register
  space (a real PPU/APU/DMA register write has hardware side effects a silent poke can't model
  without either faking them or breaking the determinism contract), so widening reads while
  keeping writes WRAM-scoped is a deliberate, asymmetric choice, not an oversight.

Deferred (honestly scoped, not silently dropped)

• A wasm piccolo Lua backend (scripting is currently native-only, mlua) and TAStudio-style
  piano-roll movie editing are both substantial standalone efforts, comparable in size to a full
  release rung on their own — pushed to a later, explicitly-scoped release rather than folded into
  this one. See to-dos/VERSION-PLAN.md's v1.9.0 section.