Add descriptive tooltips to MIDI CC Rack knobs

[adalvi18]

• Added a getMidiCCName helper function in an anonymous namespace within MidiCCRackView.cpp to resolve standard MIDI CC designations defined in include/Midi.h.
• Updated the MidiCCRackView constructor to fetch these descriptive names and apply them as tooltips to the individual Knob widgets.
• If a CC has a standard name, hovering over the knob will now display something like CC 1: Modulation Wheel or CC 7: Main Volume. If no standard name exists, it simply falls back to the default CC #.
• The visual layout of the rack remains unaffected to keep the interface clean, with the new information unobtrusively accessible via hover.

Fixes #8354