feat: support inline background transforms

[han4wluc]

Summary

• Add inline background transform overrides for x/y, anchor, scale, rotation, originX, and originY
• Preserve current background resources when a line only patches background transform fields
• Include inline background transforms in render output and presentation change diffs
• Bump package version to 1.22.0

Tests

• bun run test
• bun run lint
• bun run build
• rtgl vt screenshot --wait-event vt:ready --item background/inline-transform.yaml --timeout 60000
• rtgl vt report --item background/inline-transform.yaml --compare-method md5