perf(producer): cache local font compression

[miguel-heygen]

Summary

• persist WOFF2 compression results for local TTF/OTF/TTC files in the existing HyperFrames font cache
• key entries by font content and source format so repeated CLI runs reuse identical compressed bytes
• use atomic best-effort cache writes and preserve raw-font fallback when compression fails

Performance

• 3.9 MB CJK TTF: 5316 ms cold, 3.8 ms warm
• repeated one-frame renders previously recompressed every local font on every invocation

Tests

• bun test packages/producer/src/services/fontCompression.test.ts
• bun test packages/producer/src/services/htmlCompiler.test.ts packages/producer/src/services/deterministicFonts-googleSubsets.test.ts
• bun run --cwd packages/producer typecheck
• bun run lint