Route MIDI Poly/Channel Pressure to aftertouch, not pitchBend

The 0xA0 (Poly Key Pressure) and 0xD0 (Channel Pressure) handlers
in handleMidi() were both calling setFromInt on
ParameterID::pitchBend, even though the inline comments said
'Aftertouch'. Looks like a copy-paste of the 0xE0 (pitch bend)
case that never got its parameter ID corrected.

Effect today: pressure values were silently misrouted into the
pitchBend parameter. The mismatch was nearly inaudible because the
pitchBend scale is [-8192, 8191] (14-bit) but data[2] is 0-127, so
the misrouted values produced only a tiny upward pitch drift.

Two coordinated fixes:

1. Route both 0xA0 and 0xD0 to ParameterID::aftertouch. Scales are
   already aligned: Scales::aftertouch is (0.0, 127.0) — exactly
   the MIDI value range.

2. Relax the early-return size guard from \`!= 3\` to \`< 2\`. Channel
   Pressure is a 2-byte message (status + value, no data[2]). The
   old strict-3 guard silently dropped every 0xD0 event before it
   could reach the switch, so even after the routing fix, channel
   pressure would still do nothing without this. The new floor lets
   each case rely on its own status-byte size convention; only 0xD0
   actually needs the 2-byte allowance, the other cases still
   inspect data[2] safely because all their status bytes mean
   3-byte messages.

Poly Key Pressure (0xA0) on a monophonic synth applies globally
(there's only one note); the data[1] note-number field is ignored.

Found while looking into MPE support — pressure routing is one of
the things any MPE mapping needs to get right, so this had to be
correct first.

Author: magnetophon

plugin/dpf/DigiDrie/plugin.cpp

@@ -153,7 +153,11 @@ class DigiDrie : public Plugin {
     uint32_t &midiIndex,
     uint32_t midiEventCount)
   {
-    if (ev.size != 3) return;
+    // Channel Pressure is a 2-byte message (status + value); the
+    // earlier `!= 3` guard silently dropped every 0xD0 event. Use the
+    // minimum-2 floor and let each case rely on its own status-byte
+    // convention for how many bytes it actually inspects.
+    if (ev.size < 2) return;
 
     switch (ev.data[0] & 0xf0) {
       // Note off.
@@ -178,19 +182,20 @@ class DigiDrie : public Plugin {
         }
       } break;
 
-      // Polyphonic Key Pressure (Aftertouch).
+      // Polyphonic Key Pressure. data[1]: note, data[2]: pressure.
+      // Applied as global aftertouch since the synth is monophonic.
       case 0xA0: {
-        dsp->param.value[ParameterID::pitchBend]->setFromInt(ev.data[2]);
+        dsp->param.value[ParameterID::aftertouch]->setFromInt(ev.data[2]);
       } break;
 
       // Control Change.
       case 0xB0: {
         handleControlChange(ev, midiEvents, midiIndex, midiEventCount);
       } break;
 
-      // Channel Pressure (Aftertouch).
+      // Channel Pressure. data[1]: pressure (no data[2]; 2-byte msg).
       case 0xD0: {
-        dsp->param.value[ParameterID::pitchBend]->setFromInt(ev.data[1]);
+        dsp->param.value[ParameterID::aftertouch]->setFromInt(ev.data[1]);
       } break;
 
       // Pitch bend. Center is 8192 (0x2000).