Expose native timer ops (queueUserTimer/cancelTimer) instead of discarding them

[marciomazza]

I think it would be really useful to have a jsrun backed setTimeout and friends available somehow. (setTimeout/clearTimeout/setInterval/clearInterval)

Right now I had to hand-roll setTimeout/setInterval myself in JS using Atomics.waitAsync, which works but looks cumbersome to me.

I noticed that python_extension()'s JS bridge (src/runtime/ops.rs:278) does this:

const { ops } = Deno.core;
delete globalThis.Deno;

So it throws away queueUserTimer/cancelTimer along with everything else on Deno.core.
The timer machinery is already running inside jsrun, just out of reach.

Also noticed runner.rs already imports deno_core::stats and calls js_runtime.runtime_activity_stats_factory() to count active timers/intervals for the stats API — so you're already reaching into this exact subsystem from Rust.

Would it be reasonable to just grab the timer functions before the delete and make them available?

Perhaps something like:

const { ops, queueUserTimer, cancelTimer } = Deno.core;
globalThis.__jsrunTimers = Object.freeze({ queueUserTimer, cancelTimer });
delete globalThis.Deno;

Thanks for the great project! I'm already putting it to good use.