Fix ADB connection error caused by Rolldown bundler TDZ bug

Rolldown (Vite 8's bundler) collapses `const x = await ...; this.y = x`
into `this.y = await ...`, which moves the `this` access before `await`.
In WrapReadableStream's constructor, this happens inside a callback
called during super(), causing a TDZ violation:
"Must call super constructor in derived class before accessing 'this'"

Patch @yume-chan/stream-extra to use .then() instead of await+assignment
in WrapReadableStream, keeping `this` access inside the callback where
Rolldown cannot collapse it.

Author: evdenis