suggestion: deprecate `writableStrategy` and `readableStrategy` argument properties for `std/json` constructors

[iuioiua]

The TransformStreams in std/json are the only ones with writableStrategy and readableStrategy argument properties in their constructors. There are many other TransformStreams in the Standard Library, but none of them has these options, nor do they seem to need to. The std/json classes don't seem to be part of a special case either that justifies these properties. I think these options should be deprecated to trim needless moving parts.

[kt3k]

I feel these options can be useful when the users need to control the buffer amount at transform stream node (when downstream is slower than upstream).

@crowlKats @ayame113 What do you think?

[iuioiua]

Perhaps. But I've yet to see demand for such functionality. If so, we should do this for all other TransformStreams in the Standard Library.

[iuioiua]

What shall we do?

1. Remove all strategy options for stream implementations. I suspect zero-little demand for this functionality, so this one has my vote.
2. Ensure all streams have strategy options.

[kt3k]

Let's not decide right now, but let's keep this issue open for a while to see more thoughts/opinions

[iuioiua]

@ayame113 and @crowlKats, WDYT?

[crowlKats]

I am in favour