Initial tablet POC: project restructure + WebSocket/HTTP server + JS client

- Restructured project into /app, /server, /client with run.py entry point
- WSServer (QWebSocketServer) with log_signal, start/stop, client tracking
- HTTP server serves /client on port 8080
- Vanilla JS client: faders, toggles, transport, drag-to-arrange, lock/save layout
- Start Tablet button + floating Tablet log window in app UI
- Preset broadcast on load/switch, DAW state relay, hardware sync via widget_update
- Widget colors synced from app palette, toggle state fixed (sends 0/127 correctly)
- Layout saved per preset UUID back to presets.json

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/midi_sender.py

@@ -0,0 +1,27 @@
+import rtmidi
+from midi_receiver import midi_receiver
+
+
+MIDI_CH = 0
+TRANSPORT_MIDI_CH = 0
+
+midi_out = rtmidi.MidiOut()
+transport_midi_out = rtmidi.MidiOut()
+
+available_ports = midi_out.get_ports()
+print("Available MIDI ports:", available_ports)
+
+
+def send_cc(cc_number, value, channel=None):
+    ch = (channel - 1) if channel is not None else MIDI_CH
+    msg = [0xB0 | ch, cc_number, value]
+    if midi_out.is_port_open():
+        midi_out.send_message(msg)
+        midi_receiver.midi_out_signal.emit(msg)
+
+
+def send_transport_cc(cc_number, value):
+    msg = [0xB0 | TRANSPORT_MIDI_CH, cc_number, value]
+    if transport_midi_out.is_port_open():
+        transport_midi_out.send_message(msg)
+        midi_receiver.midi_out_signal.emit(msg)