Align renderer CLI docs with endpoint options

[dsafdsaf132]

Summary

• Add CLI coverage for Node PNG memory and render strategy options.
• Document the current renderer layer, frame, export, and prepared-layer options in the renderer README files and skill guide.
• Add CLI tests for the newly documented options and render strategy validation.

Why

The renderer package exposed some Node rendering controls in code, but the CLI endpoint and docs did not fully match that surface.

Validation

• npm --prefix packages/wasm-gerber-renderer run check
• git diff --check