Music Blocks 4 Program Builder

Music Blocks v4 has a modular architecture with a block editor, compiler, and execution engine built separately but not yet connected. This project integrates the Masonry visual block editor into the main application, implements block snapping and connection logic so users can build structured programs, and wires the full execution pipeline (blocks to AST to IR to output) so programs produce real music and graphics. Core deliverables: (1) Masonry module integration with palette and workspace (2) snap-based block connections with visual feedback enforcing programming semantics (3) end-to-end execution connecting blocks to the Painter and Singer modules via a real function registry. Stretch goals include inline block editing and workspace zoom/pan/undo.