Handle Push 2 encoder MIDI input

[joaodotwork]

Description

Receive and decode MIDI CC messages from Push 2's 8 track encoders, touch events, and navigation buttons via push2-python's mido callback thread.

Tasks

• Register @on_encoder_rotated callback for CC 71–78
• Decode relative 2's complement values (1–63 = CW, 127–64 = CCW)
• Handle encoder touch events (Note 0–7, velocity 127 = touch, 0 = release)
• Handle Page Left (CC 62) and Page Right (CC 63) for parameter bank navigation
• Handle upper display buttons (CC 102–109) and lower buttons (CC 20–27)
• Map encoder index to current parameter page slot
• Connect to Push 2 User Port (or send SysEx mode command)

Acceptance Criteria

• All 8 encoders correctly update their mapped parameter
• Touch events trigger visual highlight on the display
• Page buttons navigate through parameter banks of 8
• Works on Push 2 User Port without Ableton running

Technical Notes

Column	Encoder CC	Touch Note	Upper Button CC	Lower Button CC
1	CC 71	Note 0	CC 102	CC 20
2	CC 72	Note 1	CC 103	CC 21
...	...	...	...	...
8	CC 78	Note 7	CC 109	CC 27

Decoding: delta = value if value <= 63 else value - 128
Resolution: ~210 steps per full rotation