Add hs.midi. Closes #132

[cmsj]

• Checkpoint
• Switch to using non-deprecated APIs

[greptile-apps]

Greptile Summary

Adds the new CoreMIDI-backed hs.midi module and its generated API surface.

• Registers hs.midi with ModuleRoot and the JavaScript test harness.
• Implements physical-device and virtual-source discovery, MIDI callbacks, command encoding, SysEx handling, and resource teardown.
• Adds integration coverage for the JavaScript API, CoreMIDI communication, codec behavior, callbacks, and lifecycle.
• Updates documentation extraction to map the on-disk hs.midi_ directory to the public hs.midi namespace.

Confidence Score: 4/5

The PR is not yet safe to merge because a transient source-connection failure permanently disables input retries for that device object.

The failed MIDIPortConnectSource branch still leaves inputPort nonzero and selfRef retained, while every later non-nil setCallback call is blocked by the inputPort == 0 guard and cannot reconnect.

Files Needing Attention: Hammerspoon 2/Modules/hs.midi_/HSMIDIDevice.swift

Important Files Changed

Filename	Overview
Hammerspoon 2/Modules/hs.midi_/HSMIDIDevice.swift	Implements device I/O and callback lifecycle, but the previously reported failed-connect state still prevents retries.
Hammerspoon 2/Modules/hs.midi_/HSMIDIModule.swift	Implements module discovery, setup notifications, shared CoreMIDI resources, and a proper MainActor hop for notification callbacks.
Hammerspoon 2/Modules/hs.midi_/HSMIDIMessageCodec.swift	Implements MIDI 1.0 UMP command and SysEx encoding/decoding with bounded persistent SysEx accumulation.
Hammerspoon 2/Engine/ModuleRoot.swift	Registers hs.midi through the existing lazy module-loading mechanism.
Hammerspoon 2Tests/IntegrationTests/HSMIDIIntegrationTests.swift	Adds broad codec, JavaScript bridge, callback, virtual-source, and lifecycle integration coverage.
scripts/extract-docs.js	Maps the special hs.midi_ source directory to the public hs.midi documentation namespace.

_{Reviews (2): Last reviewed commit: "Prevent SysEx messages from potentially ..." | Re-trigger Greptile}

[cmsj]

@greptile