Initial release — InstaGrain granular synthesizer v1.0

8-voice polyphonic granular synth (VST3/AU/LV2) with:
- 128 grain pool per voice, Hann windowing, linear interpolation
- Root note selector, sample rate correction, sustain pedal (CC64)
- Scatter controls, direction modes (Fwd/Rev/PingPong), freeze
- ADSR envelope, global filter (LP/HP/BP), reverb
- Waveform display with grain visualization
- Drag & drop sample loading, full state save/restore
- CI/CD for Windows/macOS/Linux

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

Source/MasterPanel.cpp

@@ -0,0 +1,49 @@
+#include "MasterPanel.h"
+
+MasterPanel::MasterPanel()
+{
+    titleLabel.setText ("MASTER", juce::dontSendNotification);
+    titleLabel.setJustificationType (juce::Justification::centredLeft);
+    titleLabel.setColour (juce::Label::textColourId, InstaGrainLookAndFeel::textPrimary);
+    addAndMakeVisible (titleLabel);
+
+    volumeKnob.setSliderStyle (juce::Slider::RotaryHorizontalVerticalDrag);
+    volumeKnob.setTextBoxStyle (juce::Slider::TextBoxBelow, false, 55, 14);
+    volumeKnob.setRange (0.0, 2.0);
+    volumeKnob.setValue (1.0);
+    volumeKnob.getProperties().set (InstaGrainLookAndFeel::knobTypeProperty, "orange");
+    addAndMakeVisible (volumeKnob);
+
+    volLabel.setText ("Volume", juce::dontSendNotification);
+    volLabel.setJustificationType (juce::Justification::centred);
+    volLabel.setColour (juce::Label::textColourId, InstaGrainLookAndFeel::textSecondary);
+    addAndMakeVisible (volLabel);
+
+    addAndMakeVisible (vuMeter);
+}
+
+void MasterPanel::resized()
+{
+    auto bounds = getLocalBounds().reduced (4);
+    titleLabel.setBounds (bounds.removeFromTop (20));
+
+    int halfW = bounds.getWidth() / 2;
+
+    // Volume knob
+    auto knobArea = bounds.removeFromLeft (halfW);
+    auto knobRect = knobArea.withTrimmedBottom (16);
+    volumeKnob.setBounds (knobRect.reduced (2));
+    volLabel.setBounds (knobArea.getX(), knobRect.getBottom() - 2, knobArea.getWidth(), 16);
+
+    // VU meter
+    vuMeter.setBounds (bounds.reduced (8, 4));
+}
+
+void MasterPanel::paint (juce::Graphics& g)
+{
+    auto bounds = getLocalBounds().toFloat();
+    g.setColour (InstaGrainLookAndFeel::bgMedium.withAlpha (0.5f));
+    g.fillRoundedRectangle (bounds, 4.0f);
+    g.setColour (InstaGrainLookAndFeel::bgLight.withAlpha (0.3f));
+    g.drawRoundedRectangle (bounds, 4.0f, 1.0f);
+}