fix(web): do not rely on ReadableStream.from or new ReadableStream

[KnightNiwrem]

For #492

[codecov]

Codecov Report

All modified lines are covered by tests ✅

Comparison is base (a92b766) 46.51% compared to head (5bd05dd) 46.51%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #493   +/-   ##
=======================================
  Coverage   46.51%   46.51%           
=======================================
  Files          19       19           
  Lines        5615     5615           
  Branches      226      226           
=======================================
  Hits         2612     2612           
  Misses       3000     3000           
  Partials        3        3           

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[KnightNiwrem]

Please feel free to move writer.close() out of the async function, and perhaps into a .finally(...) block instead

[KnightNiwrem]

CFW should raise the compatibility date in their config, or set the feature flag: https://developers.cloudflare.com/workers/configuration/compatibility-dates/#streams-constructors