feat: optimize release build for smaller size

[alemidev]

No description provided.

[zaaarf]

Why "z" rather than any of the others? What's your reasoning? @alemidev

[alemidev]

@zaaarf while we care about integration speed in our CRDT, most of codemp's runtime is spent idle waiting either for user interaction or network I/O, so I think it's reasonable to prefer smaller binaries over faster hot sections.

I don't really have more definitive reasons to prefer size over optimization, as soon as we can notice performance issues we should revert this, but until then shaving off 66% of our binary size is quite impressive.

For reference: https://doc.rust-lang.org/cargo/reference/profiles.html#opt-level

Also, picked z over s because it results a bit smaller, but it's probably overkill