feat: add text-backed visuals

[han4wluc]

Summary

• Add text-backed visual items with validation for resourceId vs text and RouteGraphics rich text/furigana content.
• Preserve visual-level transform, layer, opacity, blur, and animations for text visuals, including patch updates by id.
• Fix background transform persistence so choosing a transformId does not inherit stale inline transform overrides, while explicit overrides still apply.
• Bump package version to 1.23.0 and document the new visual text API.

Tests

• bun run test
• bun run lint
• rtgl vt report --item visual/text