[Feature] move sol! doctest descriptions out of the code

[DaniPopes]

Component

sol-type, sol! macro

Describe the feature you would like

For rendering to markdown. Other inline comments and docs are fine.

Additional context

E.g.

This:

core/crates/sol-types/tests/doctests/contracts.rs

Lines 5 to 10 in 3eab410

	// Contracts generate a module with the same name, which contains all the items.
	// This module will also contain 3 container enums, one for each:
	// - functions: `<contract_name>Calls`
	// - errors: `<contract_name>Errors`
	// - events: `<contract_name>Events`
	sol! {

To here:

core/crates/sol-macro/src/lib.rs

Lines 62 to 63 in 3eab410

	/// ## Contracts/interfaces
	/// ```ignore