Enhance Ableton export logic with scaled note velocity and filter fader canonicalization

tests/ableton-fader-policies.test.ts

@@ -1,6 +1,7 @@
 import assert from 'node:assert/strict';
 import test from 'node:test';
 import {
+  canonicalizeFilterFaderValue,
   convertGroupFaderValue,
   FADER_POLICIES,
   getFaderPolicy,
@@ -30,3 +31,10 @@ test('uses one group-fader conversion path for mixer and pad targets', () => {
   assert.equal(convertGroupFaderValue(FaderParam.PAN, 0.75, { track }), 0.5);
   assert.equal(convertGroupFaderValue(FaderParam.PTC, 0.75, { track, valueOffset: 7 }), 9.5);
 });
+
+test('canonicalizes only effectively-open filter fader values', () => {
+  assert.equal(canonicalizeFilterFaderValue(FaderParam.LPF, 0.9996299743652344), 1);
+  assert.equal(canonicalizeFilterFaderValue(FaderParam.HPF, 0.0003700256347656), 0);
+  assert.equal(canonicalizeFilterFaderValue(FaderParam.LPF, 0.998), 0.998);
+  assert.equal(canonicalizeFilterFaderValue(FaderParam.HPF, 0.002), 0.002);
+});