[runtime/network] poison sink/stream on error and cancellation

[andresilva]

This PR changes the network Sink/Stream contract so each half is poisoned after cancellation or its first I/O error instead of being implicitly reusable in an incosistent state. A failed send now makes the Sink unusable, and a failed recv makes the Stream unusable, subsequent operations on that same half return Closed, while the opposite direction can still continue.

Related #2596 (possibly closes it?)

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[andresilva]

mock changes lgtm

[codecov]

Codecov Report

❌ Patch coverage is 94.42971% with 21 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.73%. Comparing base (54ee26b) to head (b9a1b69).

Files with missing lines	Patch %	Lines
runtime/src/mocks.rs	84.76%	15 Missing and 1 partial ⚠️
runtime/src/network/mod.rs	97.54%	4 Missing ⚠️
runtime/src/network/iouring.rs	98.38%	0 Missing and 1 partial ⚠️

@@            Coverage Diff             @@
##             main    #3501      +/-   ##
==========================================
- Coverage   95.74%   95.73%   -0.01%     
==========================================
  Files         438      438              
  Lines      157975   158264     +289     
  Branches     3706     3722      +16     
==========================================
+ Hits       151249   151517     +268     
- Misses       5541     5562      +21     
  Partials     1185     1185              

Files with missing lines	Coverage Δ
runtime/src/lib.rs	97.75% <ø> (+0.04%)	⬆️
runtime/src/network/deterministic.rs	96.29% <100.00%> (-0.85%)	⬇️
runtime/src/network/tokio.rs	89.73% <100.00%> (+0.80%)	⬆️
stream/src/utils/codec.rs	97.89% <100.00%> (+0.07%)	⬆️
runtime/src/network/iouring.rs	93.47% <98.38%> (+0.51%)	⬆️
runtime/src/network/mod.rs	98.60% <97.54%> (-0.65%)	⬇️
runtime/src/mocks.rs	94.92% <84.76%> (-4.31%)	⬇️

... and 3 files with indirect coverage changes

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