feat: add Takumi renderer support

[harlan-zw]

Summary

#411

Adds Takumi as an alternative rendering engine for OG images. Takumi is a Rust-based renderer that directly rasterizes to PNG/JPEG/WebP without SVG intermediates.

• 2-10x faster than Satori+Resvg pipeline
• Native Tailwind CSS support via tw prop
• Direct raster output (no SVG intermediate)
• Variable font and COLR emoji support
• RTL text support

Changes

New files:

• bindings/takumi/node.ts - Node.js binding
• bindings/takumi/wasm.ts - WASM binding for edge runtimes
• takumi/instances.ts - Lazy-loaded renderer instance
• takumi/nodes.ts - HTML to Takumi node converter
• takumi/renderer.ts - Main renderer implementation
• test/unit/takumiNodes.test.ts - Unit tests for node conversion

Modified files:

• types.ts - Added takumi renderer type and options
• instances.ts - Added useTakumiRenderer()
• context.ts - Added takumi case to renderer switch
• compatibility.ts - Added takumi to all runtime configs

Usage

// Per-page
defineOgImage({
  renderer: 'takumi',
  component: 'MyOgImage',
})

// Module defaults
export default defineNuxtConfig({
  ogImage: {
    defaults: {
      renderer: 'takumi'
    }
  }
})

Test plan

• Unit tests for style parsing pass
• Manual testing with actual @takumi-rs/core package once installed
• E2E tests with fixture app using takumi renderer

🤖 Generated with Claude Code

[harlan-zw]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

🤖 Generated with Claude Code

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