Fixes #733 by bringing the rewritten definitions into scope, instead of old ones

[b-studios]

See discussion in #733 for how I traced down the bug. Summary:

At the point where we dealias the binding l = m, the core tree looks like:

let l = m;
def b_k_1(r, xs) =
  // note the l here:
  let v_3 = run {link(k, v, l, r)}
  go(bitwiseShl225(level, 1), v_3, xs);
...

As it can be clearly seen, l is used in the join points b_k_....
The bindings, after rewriting look like this.

let l = m;
def b_k_1(r, xs) =
  // note the m here:
  let v_3 = run {link(k, v, m, r)}
  go(bitwiseShl225(level, 1), v_3, xs);
...

It appears the renaming was successful. However, the rewritten defs are updated in the InlineContext, which can be seen by inspecting rewrite(List[Definition])

https://github.com/effekt-lang/effekt/blob/9007b059291153c7d9279ec729d62803a7b47275/effekt/shared/src/main/scala/effekt/core/Inline.scala#L88C7-L97

and its callsite:

effekt/effekt/shared/src/main/scala/effekt/core/Inline.scala

Lines 124 to 126 in 9007b05

	case Stmt.Scope(definitions, body) =>
	val (defs, ctx) = rewrite(definitions)
	scope(defs, rewrite(body)(using ctx))

So, the next time a def is inlined, the old def is inlined. It still refers to the old, aliased but now removed, binding... Hence causing the error.

In this PR, I update the defs in the context to now contain the rewritten (dealiased) right hand sides.

[b-studios]

Looks like a few tests still fail, but I can't look into it any further today.

[jiribenes]

LGTM, thanks for the fix. The tests are only failing because of genericX, so I'll just exclude them on non-JS backends and I'll test it with the other repro. Thanks again! 🎄 🎅 🎁

EDIT: Other repro tested, seems to work!