instrument: deliver continuous playback params live to sounding voices via a seqlock block, holding normalized stage position across time edits

tests/test_deck_groups.cpp

@@ -186,7 +186,40 @@ static void testBipolarKnobLawRoundTripsAndIsExactAtCentre() {
     CHECK(deckNormFromBipolar(3.0) == 1.0);
 }
 
+static void testLiveRoutingCoversEveryContinuousPlaybackControl() {
+    // The live set: the six filter tone/modulation knobs, plus every stage time and stage
+    // level on all three envelopes.
+    const DeckParam live[] = {
+        DeckParam::kFilterMorph, DeckParam::kFilterCutoff, DeckParam::kFilterQ,
+        DeckParam::kFilterDrive, DeckParam::kFilterModAmt, DeckParam::kFilterKeyTrack,
+        DeckParam::kAttack, DeckParam::kHold, DeckParam::kDecay, DeckParam::kSustain,
+        DeckParam::kRelease,
+        DeckParam::kFilterEnvAttack, DeckParam::kFilterEnvHold, DeckParam::kFilterEnvDecay,
+        DeckParam::kFilterEnvSustain, DeckParam::kFilterEnvRelease,
+        DeckParam::kPitchEnvAttack, DeckParam::kPitchEnvDecay, DeckParam::kPitchEnvDepth,
+    };
+    for (DeckParam p : live) CHECK(isLiveDeckParam(p));
+
+    // Everything else reloads or rebuilds. kFilterVel and kKeyTrack are the two that look
+    // continuous but feed values a voice latches at note-on (the velocity-curve result and
+    // the pitch ratio) — making them live would re-gain or retune a note already struck.
+    const DeckParam reloads[] = {
+        DeckParam::kPlayMode, DeckParam::kPitchEngine, DeckParam::kPitchEnvEnable,
+        DeckParam::kFilterEnable, DeckParam::kFilterLaw, DeckParam::kFilterVel,
+        DeckParam::kKeyTrack, DeckParam::kTrigLength, DeckParam::kTrigFadeIn,
+        DeckParam::kTrigFadeOut, DeckParam::kVoiceCount, DeckParam::kVoiceMode,
+        DeckParam::kMonoTrigger, DeckParam::kMasterGain,
+    };
+    for (DeckParam p : reloads) CHECK(!isLiveDeckParam(p));
+
+    // Every id in the space is classified by one of the two lists above, so a control added
+    // later cannot slip through unclassified.
+    const std::size_t classified = (sizeof(live) + sizeof(reloads)) / sizeof(DeckParam);
+    CHECK(classified == static_cast<std::size_t>(DeckParam::kCount));
+}
+
 int main() {
+    testLiveRoutingCoversEveryContinuousPlaybackControl();
     testDeckReadsPitchThenFilterThenAmpLeftToRight();
     testFilterGroupCarriesItsFiveToneControlsPlusModulation();
     testAmpGroupWidthSurvivesAGateTriggerFlip();