docs: Std lib documentation

[stoobie]

Documentation Feature Request

The Cairo reference should have documentation of the std library. Devs were looking for info on basic operations, such as power, string manipulation, sorting arrays, and other standard language features.

It turns out that the Alexandria library does include the power operation. The docs should mention these features, even if they are unsupported, and point to other libs with support.

The Starknet crate includes many primitives (functions and methods) that need to be documented.

The Starknet library is documented partially in the Starknet Book, but this is not intuitive. It's also not documented well.

If the feature request is approved, would you be willing to submit a PR?
(Help can be provided if you need assistance submitting a PR)

• Yes
• No