fix: allow ts casts in bindings

[gtm-nayan]

fix #10179

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[dummdidumm]

There's an object method in the utils.js which I think should also get this treatment?
In general I'm wondering if we should unpack the expressions in acorn.js where we traverse the TS AST to clean up a few thing. Maybe we can also unpack/remove those AST types from the AST.

[gtm-nayan]

#10179

turns out the place that marks the binding as reassigned and mutated

svelte/packages/svelte/src/compiler/phases/scope.js

Line 636 in ecba825

for (const [scope, node] of updates) {

would also need to be updated,

I think it makes sense to unwrap everything right after parse then

[dummdidumm]

I tried removing all AST nodes right after parsing in a post-process step, but it failed because of this - if you have an idea how to solve this, I'm all ears

[gtm-nayan]

That's for removing it during parsing right? We could do one pass after the whole file is parsed.

[dummdidumm]

Mhm maybe. I removed it after an expression/the script tag was parsed, but doing it after the whole thing is parsed could maybe work.. would you mind trying it out?