Add deepStrictEqual support

[yassernasc]

WIP - missing circular support.

references and inspirations:
https://github.com/holepunchto/same-object
https://github.com/holepunchto/bare-inspect
https://github.com/chaijs/deep-eql/blob/main/index.js#L44-L89

[kasperisager]

This only scratches the surface of deep equality testing, see https://github.com/nodejs/node/blob/main/lib/internal/util/comparisons.js for the corresponding implementation in Node.js. We don't need to match that 1:1, but we should cover as much as is reasonable.

[yassernasc]

I'll double check a few more cases to cover; Currently, circular structures have false-positives for cases such as: https://github.com/nodejs/node/blob/main/test/parallel/test-assert-deep.js#L598-L607.

Edit: I let two unit tests commented, those are limitations for the simplicity of the current memoization solution.

[kasperisager]

Testing literal prototype identities won't work for cross-realm checks so we'll need additional libjs APIs for this, I'll add those. It's good enough for the initial implementation though 👌

[kasperisager]

holepunchto/libjs#51, we can handle that in a separate PR once the new APIs are out.

[kasperisager]

I've added some additional test cases that must be covered as well to bring us mostly in line with the Node.js implementation.

[yassernasc]

I named the new utility class Node to link the idea of an algorithm for graphs.

[kasperisager]

Solid progress! I added some more tests.

[yassernasc]

The comment "what matters is how many objects are reachable from the root before one repeats" gave me the hint of a possibility to simplify the strategy of memoization, and now, the comparison for cycles relies on the length of the circular objects.

The allowDuplicates flag wasn't planned at first, but it's necessary because of the quadratic loop from "deepStrictEqualArrayUnordered", as it may pass the same values multiple times to "deepStrictEqualValue" while performing a single (a, b) test.

[kasperisager]

Getting closer! I've added some more tests.