fix(review): dead silenceFlags store removed; channelModeFor extracted + tested; auto-default + drop comments corrected; v9 constant minted

tests/test_sample_map.cpp

@@ -146,6 +146,34 @@ static void testSelectChannelCountThreaded() {
     CHECK(selUn && selUn->channelCount == 0);  // unstamped -> unknown, never a guess
 }
 
+// --- channelModeFor (GA auto-default rule) -------------------------------------------
+
+static void testChannelModeForExplicitIsNeverFought() {
+    // An explicit user choice is ALWAYS returned unchanged, regardless of channelCount.
+    CHECK(channelModeFor(2, ChannelMode::Mono,   true) == ChannelMode::Mono);
+    CHECK(channelModeFor(1, ChannelMode::Stereo, true) == ChannelMode::Stereo);
+    CHECK(channelModeFor(0, ChannelMode::Stereo, true) == ChannelMode::Stereo);
+}
+
+static void testChannelModeForUnknownCountIsNoOp() {
+    // An unknown channel count (0 — an older bank entry) leaves the current mode unchanged.
+    CHECK(channelModeFor(0, ChannelMode::Mono,   false) == ChannelMode::Mono);
+    CHECK(channelModeFor(0, ChannelMode::Stereo, false) == ChannelMode::Stereo);
+}
+
+static void testChannelModeForStereoCapture() {
+    // A capture with channelCount >= 2 selects Stereo (regardless of current mode).
+    CHECK(channelModeFor(2, ChannelMode::Mono,   false) == ChannelMode::Stereo);
+    CHECK(channelModeFor(2, ChannelMode::Stereo, false) == ChannelMode::Stereo);
+    CHECK(channelModeFor(6, ChannelMode::Mono,   false) == ChannelMode::Stereo);
+}
+
+static void testChannelModeForMonoCapture() {
+    // A capture with channelCount == 1 selects Mono (ingest-imported mono files only).
+    CHECK(channelModeFor(1, ChannelMode::Stereo, false) == ChannelMode::Mono);
+    CHECK(channelModeFor(1, ChannelMode::Mono,   false) == ChannelMode::Mono);
+}
+
 static void testSelectEmptyBlob() {
     CHECK(!selectSample("", "a").has_value());
 }
@@ -2100,6 +2128,10 @@ int main() {
     testSelectLoopThreaded();
     testSelectNoLoopIsAbsent();
     testSelectChannelCountThreaded();
+    testChannelModeForExplicitIsNeverFought();
+    testChannelModeForUnknownCountIsNoOp();
+    testChannelModeForStereoCapture();
+    testChannelModeForMonoCapture();
     testSelectEmptyBlob();
     testSelectMalformedBlob();
     testSelectZeroSamples();