Improve phrasing and styling in some sections of README.md (#469)

## Description

This PR adds minor styling fixes, corrects RN version and rephrases a
few sections.

### Type of change

- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [x] Documentation update (improves or adds clarity to existing
documentation)

### Tested on

- [ ] iOS
- [ ] Android

### Testing instructions

<!-- Provide step-by-step instructions on how to test your changes.
Include setup details if necessary. -->

### Screenshots

<!-- Add screenshots here, if applicable -->

### Related issues

<!-- Link related issues here using #issue-number -->

### Checklist

- [x] I have performed a self-review of my code
- [x] I have commented my code, particularly in hard-to-understand areas
- [x] I have updated the documentation accordingly
- [x] My changes generate no new warnings

### Additional notes

<!-- Include any additional information, assumptions, or context that
reviewers might need to understand this PR. -->

Author: msluszniak

README.md

@@ -9,11 +9,11 @@
 
 ![Software Mansion banner](https://github.com/user-attachments/assets/fa2c4735-e75c-4cc1-970d-88905d95e3a4)
 
-**React Native ExecuTorch** is a declarative way to run AI models in React Native on device, powered by **ExecuTorch** :rocket:. It offers out-of-the-box support for many LLMs, computer vision models, and many many more. Feel free to check them out on our [HuggingFace page](https://huggingface.co/software-mansion).
+**React Native ExecuTorch** provides a declarative way to run AI models on-device using React Native, powered by **ExecuTorch** :rocket:. It offers out-of-the-box support for a wide range of LLMs, computer vision models, and more. Visit our [HuggingFace](https://huggingface.co/software-mansion) page to explore these models.
 
-**ExecuTorch** is a novel framework created by Meta that enables running AI models on devices such as mobile phones or microcontrollers. 
+**ExecuTorch**, developed by Meta, is a novel framework allowing AI model execution on devices like mobile phones or microcontrollers.
 
-React Native ExecuTorch bridges the gap between React Native and native platform capabilities, allowing developers to run AI models locally on mobile devices with state-of-the-art performance, without requiring deep knowledge of native code or machine learning internals.
+React Native ExecuTorch bridges the gap between React Native and native platform capabilities, enabling developers to efficiently run local AI models on mobile devices. This can be achieved without the need for extensive expertise in native programming or machine learning.
 
 [![npm version](https://img.shields.io/npm/v/react-native-executorch?color=00008B)](https://www.npmjs.com/package/react-native-executorch)
 [![CI](https://github.com/software-mansion/react-native-executorch/actions/workflows/ci.yml/badge.svg)](https://github.com/software-mansion/react-native-executorch/actions/workflows/ci.yml)
@@ -33,18 +33,18 @@ React Native ExecuTorch bridges the gap between React Native and native platform
 The minimal supported version are: 
 * iOS 17.0
 * Android 13
-* React Native 76
+* React Native 0.76
 
 > [!IMPORTANT]  
 > React Native Executorch supports only the [New React Native architecture](https://reactnative.dev/architecture/landing-page).
 
 ## :robot: Ready-made models
 
-To run any AI model in ExecuTorch, you need to export it to a `.pte` format. If you're interested in experimenting with your own models, we highly encourage you to check out the [Python API](https://pypi.org/project/executorch/). If you prefer focusing on developing your React Native app, we will cover several common use cases. For more details, please refer to the documentation.
+Our library has a number of ready-to-use AI models; a complete list is available in the documentation. If you're interested in running your own AI model, you need to first export it to the `.pte` format. Instructions on how to do this are available in the [Python API](https://pypi.org/project/executorch/).
 
 ## :books: Documentation
 
-Take a look at how our library can help build you your React Native AI features in our docs:  
+Check out how our library can help you build your React Native AI features by visiting our docs:  
 https://docs.swmansion.com/react-native-executorch
 
 ## :llama: **Quickstart - Running Llama**
@@ -68,17 +68,11 @@ Add this to your component file:
 import {
   useLLM,
   LLAMA3_2_1B,
-  LLAMA3_2_TOKENIZER,
-  LLAMA3_2_TOKENIZER_CONFIG,
 } from 'react-native-executorch';
 
 function MyComponent() {
   // Initialize the model 🚀
-  const llm = useLLM({
-    modelSource: LLAMA3_2_1B,
-    tokenizerSource: LLAMA3_2_TOKENIZER,
-    tokenizerConfigSource: LLAMA3_2_TOKENIZER_CONFIG,
-  });
+  const llm = useLLM({ model: LLAMA3_2_1B });
   // ... rest of your component
 }
 ```
@@ -132,6 +126,6 @@ To learn about our upcoming plans and developments, please visit our [milestones
 
 ## React Native ExecuTorch is created by Software Mansion
 
-Since 2012 [Software Mansion](https://swmansion.com) is a software agency with experience in building web and mobile apps. We are Core React Native Contributors and experts in dealing with all kinds of React Native issues. We can help you build your next dream product – [Hire us](https://swmansion.com/contact/projects?utm_source=react-native-executorch&utm_medium=readme).
+Since 2012, [Software Mansion](https://swmansion.com) is a software agency with experience in building web and mobile apps. We are Core React Native Contributors and experts in dealing with all kinds of React Native issues. We can help you build your next dream product – [Hire us](https://swmansion.com/contact/projects?utm_source=react-native-executorch&utm_medium=readme).
 
 [![swm](https://logo.swmansion.com/logo?color=white&variant=desktop&width=150&tag=react-native-executorch-github 'Software Mansion')](https://swmansion.com)