fix(renderer): restore small solid primitives

[agustin-littlehat]

Summary

• Restore smaller canonical solid primitive sizes for quad, triangle, large border-triangle, and border-shape render paths.
• Mirror the renderer/style/snapshot changes across vanilla, React, and Vue copies.
• Update tests and AGENTS.md to match the restored primitive sizes.

Verification

• pnpm test && pnpm build
• Reproduced the deployed Android mobile home flicker with screenshots, then verified local Android-sized screenshots stayed stable while rotation remained enabled.