Played with Whack™ AS3 verifier

[hydroperfox]

I've fixed the bugs in the Whack™'s ActionScript 3 verifier. Played with Whack packages in the structure of a package manager.

In difference to my previous verifiers, this one throws deferring errors in Rust which cause more cycles to run the type checker.

Here's an example program:

import whack.utils.*;

trace("Hello, world");

// does not exist!
whack.utils.f

// exists...
new whack.utils.ByteArray();

// unused!
var x = 10;

(The Whack libraries including AS3 language globals are loaded before this demonstration package.)

Verification output after running cargo run -p whackengine-whack -- check --path demo --builtins ../whacklib/packages/whack.base in the SDK workspace:

Note that this AS3 verifier will handle Bindable and other Whack framework's meta-data later.

MXML and CSS3 will be handled later, as well.

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Now, I'm thinking of implementing IDE integration for AS3 (language server), so that I can implement whack.base with inlay hints, autocompletion and live diagnostics.