feat(atoms): improve proxies, esp sets with mutate shorthand

[bowheart]

Description

When a signal contains a JS Set, normal mutation operations work on it, e.g.:

const signal = ecosystem.signal(new Set(['foo']))

signal.mutate(draft => {
  draft.add('bar')
  draft.delete('foo')
})

But .mutate's shorthand forms are unable to perform these operations:

signal.mutate(new Set(['bar'])) // should remove 'foo' and add 'bar'
signal.mutate(draft => new Set(['bar'])) // same

It isn't straightforward that this isn't supported. We can support this. So now we do.

While I was in there, I also added these changes:

• Prevent adding transactions for every unchanged value passed to the .mutate shorthands. This highly optimizes spread operations - e.g.

  signal.mutate(state => [...state, 'newItem'])
  // this now has pretty much the exact same behavior as:
  signal.mutate(state => {
    state.push('newItem')
  })

• Prevent recursing deeper when object refs match

• Adjust types to accept an array pluck shorthand:

  const signal = ecosystem.signal(['foo', 'bar'])
  signal.mutate({ 1: 'baz' }) // changes the item at index 1 ('bar') to 'baz'

  This worked previously, but the types didn't reflect it. Now they do.