fix: media-key tap no longer captures other devices' volume/mute keys

[greghughespdx]

Summary

Stops the media-key interceptor from capturing volume/mute/media keys that belong to other input devices. While HyperVibe is running today, every keyboard's volume keys, mute key, and volume HUD stop working normally — this fixes that.

Problem

MediaKeyInterceptor installs a system-wide HID event tap for media keys. At that level there is no device identity: the tap sees the same events for a Magic Keyboard's volume keys as for anything remote-related. The current handler then:

1. Routes any media key from any device into the app's remote button mappings — so a keyboard's volume-up key executes whatever the remote's volume-up button is mapped to
2. Consumes every media-key event unconditionally, even when no mapping exists — so the keyboard's mute key does nothing at all, and the system volume HUD never appears

The result is that simply having HyperVibe running breaks normal keyboard volume/mute behavior system-wide. This also silently eats media-key events synthesized by other software.

Solution

Invert the consume condition. The interceptor now consumes an event only when it correlates with a button press just observed on the remote's own seized HID interface (the existing 0.2s debounce check) — those are remote-origin duplicates whose action the HID path already executed, and macOS's default handling shouldn't also fire for them. Every other media-key event passes through untouched, restoring native volume, mute, and HUD behavior for all other devices.

The mapping-execution path is removed from the interceptor entirely: remote buttons are already handled by the seized HID interface, so the tap's only remaining job is suppressing remote-origin duplicates.

One deliberate behavior change: if the app ever fails to seize the remote, its presses now fall through to macOS default media handling instead of executing the mapped action. That's the correct failure mode — events the app doesn't own are no longer trapped.

Testing

• Reproduced on a Mac Studio: with the current code running, keyboard volume keys execute remote mappings, mute is dead, no HUD
• After the fix: keyboard volume/mute/HUD fully native while the app runs
• Verified pass-through directly: a synthesized volume-key event reaches macOS and steps the volume normally with the app running
• Remote buttons unaffected (still handled via the seized HID interface)