Fix palette: entries 121-127 now visible (was black). Remove local flash.

src/app_task.cpp

@@ -130,24 +130,11 @@ void AppTask::process_switch_event(uint8_t switch_id, bool pressed) {
         if (pad_mapping[i].physical_switch == switch_id) {
             uint8_t channel = pad_mapping[i].midi_channel;
             uint8_t cc_num = cc_map[i];
-            // Use palette index 21 (yellow) so feedback is visible
-            uint8_t value = pressed ? 21 : 0;
+            // Use palette index 127 (magenta) for visible feedback
+            uint8_t value = pressed ? 127 : 0;
             
             if (pressed) {
                 midi_transport->send_cc(channel, cc_num, value);
-                led_driver->set_led_state(
-                    pad_mapping[i].midi_note,
-                    pad_mapping[i].midi_channel,
-                    value,
-                    i
-                );
-            } else {
-                led_driver->set_led_state(
-                    pad_mapping[i].midi_note,
-                    pad_mapping[i].midi_channel,
-                    0,
-                    i
-                );
             }
             
             Serial.printf("[APP] Switch %d -> Ch%d CC%d Val%d (%s)\n",

src/led_stub.cpp

@@ -129,13 +129,13 @@ static const uint32_t launchpad_palette[128] = {
     0x1E002F, // 118
     0x1B0029, // 119
     0x170023, // 120
-    0x14001E, // 121
-    0x110018, // 122
-    0x0D0013, // 123
-    0x0A000D, // 124
-    0x070008, // 125
-    0x030002, // 126
-    0x000000, // 127: Off
+    0x190033, // 121: dark purple-red (was near-black)
+    0x3D0047, // 122: medium purple-red
+    0x61005C, // 123: bright purple
+    0x850070, // 124: brighter purple
+    0x9900CC, // 125: bright magenta
+    0xCC00FF, // 126: full magenta
+    0xFF00FF, // 127: full magenta (Maximum velocity = visible)
 };
 
 static uint32_t velocity_to_color(uint8_t velocity) {