jsx precompile option isn't mentioned in docs

[ry]

https://deno.com/blog/v1.38#fastest-jsx-transform

also note the warning in hono's docs https://hono.dev/docs/middleware/builtin/jsx-renderer#userequestcontext

[dmint789]

I also just stumbled upon this. The docs should mention what this means, since this is not one of the options in tsconfig.json docs.