Mega Man X4 Recompiled — v0.1.1-coop-playtest.3

Two-player co-op regression update for Windows and Linux. Unified remains
the default; online Split cameras remain experimental.

• P2 owns its pause menu and can resume it. Native world drawing, charge
  glow/projectiles, saber hits, dash trails and water effects survive pause.
• Both players' jump/hurt sounds can overlap through independent voices.
• P2 can activate enemies and Web Spider's secret-hole camera.
• Intro, Jet Stingray and Cyber Peacock handoffs retain living players at
  native landing heights. Cyber orbs prevent withdrawal while captured.
  Jet uses one READY actor, and a dead P2 stays dead across its sections.
• Victory has one campaign reward and departure. P1 owns persistent progress
  and upgrades; boss clears agree in Continue, native cards and grey portraits.
  Fresh stage selection resets carry state so re-entry cannot inherit a corpse.
• Playtest Diagnostics defaults on, displaying both accepted input streams
  and recording inputs plus starting memory cards/mod choices under
  saves/diagnostics. Offline replay requires the matching build and settings.

The numbered regression checklist has all
26 outcomes checked. Validation includes all 16 title CTests, hidden original
disc scenarios, a two-boss native save/cold-load loop, and matching two-peer
development netplay state through tick 6,253. These checks cover the reported
cases; they do not establish complete campaign coverage. Split performance
and an intermittent netplay watchdog stall remain open investigations.

The Windows/Linux launcher lobby, two local controller assignments, stacked
default HUD and Side by side option remain available. Use the same release
on both peers. Co-op requires OpenGL and a fresh boot after changing mods.