Initial commit: InstaDrums VST3 drum sampler plugin

- 12-pad drum sampler with 4x3 grid (expandable by 4)
- Velocity layers with round-robin (Salamander-style filename parsing)
- Rhythm Engine-style GUI: pad grid (left), sample editor (right top),
  FX panel (right bottom), master panel (bottom)
- Waveform thumbnails on pads + large waveform in sample editor
- ADSR envelope, pitch, pan per pad
- Drag & drop sample/folder loading
- Kit save/load (.drumkit XML presets)
- Load Folder with smart name matching (kick, snare, hihat, etc.)
- Choke groups, one-shot/polyphonic mode
- Dark modern LookAndFeel with neon accent colors
- Built with JUCE framework, CMake, MSVC 2022

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

Source/LookAndFeel.cpp

@@ -0,0 +1,44 @@
+#include "LookAndFeel.h"
+
+InstaDrumsLookAndFeel::InstaDrumsLookAndFeel()
+{
+    setColour (juce::ResizableWindow::backgroundColourId, bgDark);
+    setColour (juce::Label::textColourId, textPrimary);
+    setColour (juce::TextButton::buttonColourId, bgMedium);
+    setColour (juce::TextButton::textColourOffId, textPrimary);
+}
+
+void InstaDrumsLookAndFeel::drawRotarySlider (juce::Graphics& g, int x, int y, int width, int height,
+                                               float sliderPos, float rotaryStartAngle,
+                                               float rotaryEndAngle, juce::Slider& slider)
+{
+    auto bounds = juce::Rectangle<int> (x, y, width, height).toFloat().reduced (2.0f);
+    auto radius = std::min (bounds.getWidth(), bounds.getHeight()) / 2.0f;
+    auto centreX = bounds.getCentreX();
+    auto centreY = bounds.getCentreY();
+    auto angle = rotaryStartAngle + sliderPos * (rotaryEndAngle - rotaryStartAngle);
+
+    // Background arc
+    juce::Path bgArc;
+    bgArc.addCentredArc (centreX, centreY, radius - 2, radius - 2,
+                          0.0f, rotaryStartAngle, rotaryEndAngle, true);
+    g.setColour (bgLight);
+    g.strokePath (bgArc, juce::PathStrokeType (3.0f, juce::PathStrokeType::curved,
+                                                juce::PathStrokeType::rounded));
+
+    // Value arc
+    juce::Path valueArc;
+    valueArc.addCentredArc (centreX, centreY, radius - 2, radius - 2,
+                             0.0f, rotaryStartAngle, angle, true);
+    g.setColour (accent);
+    g.strokePath (valueArc, juce::PathStrokeType (3.0f, juce::PathStrokeType::curved,
+                                                   juce::PathStrokeType::rounded));
+
+    // Pointer
+    juce::Path pointer;
+    auto pointerLength = radius * 0.5f;
+    pointer.addRectangle (-1.5f, -pointerLength, 3.0f, pointerLength);
+    pointer.applyTransform (juce::AffineTransform::rotation (angle).translated (centreX, centreY));
+    g.setColour (textPrimary);
+    g.fillPath (pointer);
+}