docs: Add Core Library to introduction section of the Sway book (#6193)

## Description
https://fuellabs.slack.com/archives/C031TTYJM60/p1719402172570099

## Checklist

- [ ] I have linked to any relevant issues.
- [x] I have commented my code, particularly in hard-to-understand
areas.
- [x] I have updated the documentation where relevant (API docs, the
reference, and the Sway book).
- [x] If my change requires substantial documentation changes, I have
[requested support from the DevRel
team](https://github.com/FuelLabs/devrel-requests/issues/new/choose)
- [ ] I have added tests that prove my fix is effective or that my
feature works.
- [ ] I have added (or requested a maintainer to add) the necessary
`Breaking*` or `New Feature` labels where relevant.
- [x] I have done my best to ensure that my PR adheres to [the Fuel Labs
Code Review
Standards](https://github.com/FuelLabs/rfcs/blob/master/text/code-standards/external-contributors.md).
- [x] I have requested a review from the relevant team or maintainers.

---------

Co-authored-by: IGI-111 <igi-111@protonmail.com>

docs/book/spell-check-custom-words.txt

@@ -210,4 +210,9 @@ namespacing
 unsafety
 prioritizations
 polymorphism
-ContractId
+ContractId
+booleans
+underflows
+Codec
+bool
+str

docs/book/src/SUMMARY.md

@@ -7,6 +7,7 @@
   - [The Fuel Toolchain](./introduction/fuel_toolchain.md)
   - [A Forc Project](./introduction/forc_project.md)
   - [Standard Library](./introduction/standard_library.md)
+  - [Core Library](./introduction/core_library.md)
   - [Sway Language Standards](./introduction/sway_standards.md)
 - [Examples](./examples/index.md)
   - [Counter](./examples/counter.md)

docs/book/src/introduction/core_library.md

@@ -0,0 +1,30 @@
+# Core Library
+
+The Sway Core Library, like the name suggests contains core operators and logic for the primitive types of the Sway programming language. These traits and methods are an extension of the [primitive types](https://docs.fuel.network/docs/sway/basics/built_in_types/#primitive-types) `u8`, `u16`, `u32`, `u64`, `u256`, `str[]`, `str`, `bool` and , `b256` and can be used where appropriate.
+
+The latest core library documentation can be found [here](https://fuellabs.github.io/sway/master/core/). If the latest version is not compatible please refer to the appropriate tagged release.
+
+## Using the Core Library
+
+Core library functionalities do not need to be explicitly imported and will work out of the box after creating any new Sway project with [`forc new`](../forc/commands/forc_new.md). The `use` keyword is simply not required.
+
+Consider this example of using the modulo function for two like value types:
+
+```sway
+let val_1 = 10;
+let val_2 = 2;
+let result = val_1 % val_2;
+```
+
+## Core Library Prelude
+
+The prelude contains a list of operations essential to all Sway programs. The latest version of the prelude can be found [here](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/prelude.sw).
+
+- [`core::primitives::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/primitives.sw)
+- [`core::primitive_conversions::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/primitive_conversions.sw)
+- [`core::raw_ptr::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/raw_ptr.sw)
+- [`core::raw_slice::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/raw_slice.sw)
+- [`core::ops::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/ops.sw)
+- [`core::storage::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/storage.sw)
+- [`core::str::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/str.sw)
+- [`core::codec::*`](https://github.com/FuelLabs/sway/blob/master/sway-lib-core/src/codec.sw)

docs/book/src/introduction/index.md

@@ -6,4 +6,5 @@ To get started with Forc and Sway smart contract development, install the Fuel t
 - [The Fuel Toolchain](./fuel_toolchain.md)
 - [A Forc Project](./forc_project.md)
 - [Standard Library](./standard_library.md)
+- [Core Library](./core_library.md)
 - [Sway Language Standards](./sway_standards.md)