quic/stream: create gen. getWriter for stream/iter

[martenrichter]

The get writer method of QuicStream is mostly
generell enough to be usuable in other contexts.
This PR is an attempt to move the code out
of the QuicStream object to be usuable in other
parts of node.js.

Fixes #66508

[nodejs-github-bot]

Review requested:

• @nodejs/quic

[martenrichter]

@jasnell @pimterry
That is a first idea of how to move get writer out of QuicStream .
After the interface is discussed and agreed upon, I would then, in another commit, move the code for this part to a place related to stream/iter (where?).
We also need to discuss whether this should remain an internal method or part of the public api.
(In this case, additional checks are necessary)

[martenrichter]

P.S.: There seem to be some bugs remaining. (I thought I had run all tests, but it seems that I only ran lint and not a full build.) But discussing the structure should work anyway.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.43%. Comparing base (2bcc5dd) to head (8a94755).
⚠️ Report is 160 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66513      +/-   ##
==========================================
+ Coverage   90.41%   90.43%   +0.01%     
==========================================
  Files         791      792       +1     
  Lines      275567   276692    +1125     
  Branches    52835    53110     +275     
==========================================
+ Hits       249159   250224    +1065     
- Misses      16813    16861      +48     
- Partials     9595     9607      +12     

Files with missing lines	Coverage Δ
lib/internal/quic/quic.js	100.00% <100.00%> (ø)
lib/internal/quic/writer.js	100.00% <100.00%> (ø)

... and 89 files with indirect coverage changes

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[martenrichter]

Ok, now, everything works according to the local tests.

[martenrichter]

I do not understand the build failures. It complains about an unknown compiler option? Do I need to rebase?

[pimterry]

Looks like yes - it's complaining about --allow-overwriting-for-next-flag which I can see has since been dropped: #66524. Looks like this all relates to a recent V8 update.

That said, you'll then run into a separate issue, because that same V8 update has also independently broken the QUIC build 😆. Fix for that landing shortly, it's here: #66603

[martenrichter]

I have moved getWriter a separate file. It is not in the right place; I think it should go somewhere in the stream/iter dirs.

(I have not rebased, as the fixes for building quic are not on main yet).