Added contributing guidelines

Added contributing guidelines in CONTRIBUTING.md
Added thanks section in the README file to sponsors and contributors

CONTRIBUTING.md

@@ -0,0 +1,47 @@
+# Contributing to Endurain
+
+Thank you for considering contributing to Endurain! Your involvement helps improve the project and ensures it remains useful for others. Below are guidelines to make your contribution process smooth and effective.
+
+## How Can You Contribute?
+
+### 1. Start Small, Think Big
+- **Small Contributions First**: I encourage small, incremental improvements. Whether it's fixing a typo, enhancing documentation, or optimizing a small part of the code, your contribution matters. Smaller contributions are easier to review, merge, and deploy.
+- **Build Up Gradually**: As you familiarize yourself with the project, feel free to take on more complex tasks. However, starting small ensures that changes are manageable and can be quickly integrated.
+
+### 2. Issues and Bugs
+- **Report an Issue**: Found a bug? Please create an issue with detailed steps to reproduce it. If you can, propose a solution or submit a pull request (PR) with the fix.
+- **Fix an Issue**: Browse through the list of open issues. Look for ones labeled as `good first issue` or `help wanted` if you're unsure where to start.
+
+### 3. Documentation
+- **Improve Documentation**: Whether it's enhancing existing documentation or adding new sections, contributions to the documentation are highly valued. Clear and comprehensive documentation benefits everyone.
+- **Comment Your Code**: When submitting code changes, include comments where necessary. This helps maintain the code's readability and ease of understanding for future contributors.
+
+### 4. Feature Requests
+- **Suggest a Feature**: If you have an idea for a new feature, feel free to open an issue to discuss it. Please explain the use case and how it can benefit the project.
+- **Start with Discussion**: Major changes or new features should be discussed in an issue before implementation. This ensures that the proposed changes align with the project goals and direction.
+
+### 5. Code Quality and Testing
+- **Follow Code Standards**: Maintain consistency with the existing codebase. Follow any coding standards or styles used in the project.
+- **Write Tests**: If applicable, include tests for your changes. This helps ensure that the project remains stable and that new changes don't introduce bugs.
+- **Review and Refactor**: Consider reviewing and refactoring existing code to improve performance, readability, or maintainability.
+
+## Getting Started
+
+1. **Fork the Repository**: Create a fork of the project repository to work on your changes.
+2. **Clone the Repository**: Clone your forked repository to your local machine.
+   ```bash
+   git clone https://github.com/joaovitoriasilva/endurain.git
+   ```
+3. **Create a Branch**: Create a new branch for your changes.
+    ```bash
+    git checkout -b feature/your-feature-name
+    ```
+4. **Make Your Changes**: Commit your changes with clear and descriptive commit messages.
+5. **Push Your Changes**: Push your changes to your forked repository.
+    ```bash
+    git push origin feature/your-feature-name
+    ```
+6. **Submit a Pull Request**: Open a pull request (PR) to the main repository. Be sure to describe your changes and link to any relevant issues.
+
+## Thank You!
+Your contributions, whether big or small, make a huge difference. Thank you for helping to make Endurain better!

README.md

@@ -54,14 +54,12 @@ To do features (not by order):
  - Notifications logic
  - Activity Pub integration?
 
----
 # Integrate with your application
 Endurain starting on version 0.3.0 supports multiple app types. For web applications the backend will return the access and refresh tokens as http only cookies, for mobile it will return them in the response.
 To support this in your implementation you will need to:
  - Add a "X-Client-Type" header to every request with the "web" or "mobile" value. Every other value will return a 403. This will be needed for token creation and refresh logic but also for every other endpoint token validation/expiration logic
  - For activity upload currently only the "/activities/create/upload" endpoint is available and it expects a .gpx file
 
----
 # Frontend
 Table bellow shows supported environment variables. Variables marked with optional "No" should be set to avoid errors.
 
@@ -76,7 +74,6 @@ Frontend dependencies:
  - User avatars create using DiceBear (https://www.dicebear.com) avataaars style.
  - Logo created on Canva
 
----
 # Backend
 Table bellow shows supported environment variables. Variables marked with optional "No" should be set to avoid errors.
 
@@ -114,7 +111,13 @@ MYSQL_PASSWORD | changeme | `No` | N/A
 
 To check Python backend dependencies used, use poetry file (pyproject.toml)
 
- ---
 # Strava integration
 For Strava integration API endpoint must be available to the Internet.
-You will also need to create a API Application using a Strava account -> more info here https://developers.strava.com/docs/getting-started/
+You will also need to create a API Application using a Strava account -> more info here https://developers.strava.com/docs/getting-started/
+
+# Sponsors
+A huge thank you to this project sponsor(s)! Your support is greatly appreciated and helps drive the continued development and improvement of this project.
+
+If you find this project useful, please consider [sponsoring it on GitHub](https://github.com/sponsors/joaovitoriasilva). Your support will help ensure its continued development and maintenance.
+
+Thank you to all, sponsors and contributors, who make this project possible!