Per-pad FX chain, animated toggles, GR meter, simplified master panel

- FX moved from master bus to per-pad processing:
  each pad has its own Filter, Distortion, EQ, Compressor, Reverb
  via DrumPad::applyPadFx() with temp buffer rendering
- FxPanel now edits the selected pad's FX parameters
- Animated toggle switches with smooth lerp transition and glow
- Per-pad compressor GR meter connected to FxPanel display
- Master panel simplified: Volume/Tune/Pan + Limiter toggle + VU meter
- Master bus chain: Vol/Pan → Output Limiter (0dB brickwall) → VU
- Pointer glow reduced to half intensity (4 layers, narrower spread)
- Smooth 8-layer arc glow with exponential opacity falloff

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Source/PluginProcessor.h

@@ -52,16 +52,8 @@ public:
     std::atomic<float> masterPan    { 0.0f };
     std::atomic<float> masterTune   { 0.0f };
 
-    // FX params
-    std::atomic<float> compThreshold { -12.0f };
-    std::atomic<float> compRatio     { 4.0f };
-    std::atomic<float> eqLo  { 0.0f };
-    std::atomic<float> eqMid { 0.0f };
-    std::atomic<float> eqHi  { 0.0f };
-    std::atomic<float> distDrive { 0.0f };
-    std::atomic<float> distMix   { 0.0f };
-    std::atomic<float> reverbSize  { 0.3f };
-    std::atomic<float> reverbDecay { 0.5f };
+    // Master bus
+    std::atomic<bool> outputLimiterEnabled { true };
 
     // VU meter levels (written by audio thread, read by GUI)
     std::atomic<float> vuLevelL { 0.0f };
@@ -72,13 +64,6 @@ private:
     int numActivePads = defaultNumPads;
     juce::AudioFormatManager formatManager;
 
-    // Master FX chain
-    juce::dsp::Reverb reverb;
-    juce::dsp::Compressor<float> compressor;
-    juce::dsp::IIR::Filter<float> eqLoFilterL, eqLoFilterR;
-    juce::dsp::IIR::Filter<float> eqMidFilterL, eqMidFilterR;
-    juce::dsp::IIR::Filter<float> eqHiFilterL, eqHiFilterR;
-
     double currentSampleRate = 44100.0;
 
     void initializeDefaults();