Fix Doom audio on Windows and preserve Linux behavior

[frankischilling]

Part of #13

What to build

Verify Doom audio on Windows-hosted Cupid OS builds and compare it with Linux. The problem may already be fixed, so begin by testing the current bootstrap branch. If audio works, record the evidence and add enough regression coverage to keep it working. If it still fails, reproduce and fix the actual runtime path rather than disabling the feature or omitting it on one platform.

Acceptance criteria

• Test the current Windows build first to determine whether the reported Doom audio problem still exists.
• If it is already fixed, record the working configuration, runtime evidence, and the change or behavior that resolved it where this can be determined.
• If it still fails, capture a reproducible Windows failure with enough logs to identify the broken audio path.
• Confirm the equivalent Linux build and runtime baseline before making any corrective change.
• Fix any remaining shared or platform-specific cause without weakening Doom, audio, or bootstrap behavior.
• Add focused regression coverage for the verified behavior where automation can observe it.
• Run Doom with audio on Windows and Linux and record the tested host, image, launch path, and result.
• Verify that non-Doom audio and a normal boot still work.
• Update the wiki and CTXT documentation with supported audio behavior and troubleshooting information.

Blocked by

• Bootstrap Cupid OS with a self-hosting Cupid toolchain #13

This work starts after the self-hosting bootstrap is complete and must finish before the bootstrap branch merges to main.