feat(svg): add native p5.svg experimental feature module and contributor docs - #9123

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@11d5960a326750d5838078e36cf38b85af677262, actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

src/strands/strands_api.js:8:3: Identifier 'TypeInfoFromGLSLName' is imported but never used.

src/webgl/3d_primitives.js:1956:11: Variable 'prevOrder' is declared but never used.

src/strands/ir_dag.js:152:10: Function 'getNodeKey' is declared but never used.

src/strands/ir_dag.js:5:3: Identifier 'StatementType' is imported but never used.

test/unit/core/sketch_overrides.js:4:9: Variable 'mockP5' is declared but never used.

src/strands/strands_conditionals.js:4:10: Identifier 'StrandsNode' is imported but never used.

src/strands/strands_codegen.js:7:3: Identifier 'TypeInfoFromGLSLName' is imported but never used.

src/strands/strands_codegen.js:5:3: Identifier 'StatementType' is imported but never used.

src/strands/strands_codegen.js:4:3: Identifier 'NodeType' is imported but never used.