docs: add Git branching best practices and optimize Netlify deployment instructions

[Grajales-K]

Revised PR Description
Problem: Currently, the instructions do not introduce GitHub Pages for early deployment, leading to unnecessary consumption of Netlify build credits. Additionally, the Level 500 instructions lack explicit guidance on feature branches and final deployment setup.

Changes:

Level 0: Replaced Netlify with GitHub Pages for initial deployment to provide a free, unlimited hosting option during early development.

Level 500: * Moved Netlify deployment instructions here as the final "production" step.

Added a detailed Step-by-Step guide for Netlify setup (since it was removed from Level 0).

Added a "Technical Workflow" section to encourage the use of feature branches (feature/level-500) after merging Level 400.

Aligned instructions with dashboard submission requirements to reduce student confusion.

[illicitonion]

Generally LGTM - let's avoid repeating the contents of the deployment guides here, so that if the steps need to change (e.g. if Netlify change their screens) we only need to update one place not multiple.

[illicitonion]

Suggested change

	To keep your project visible from the start without exhausting Netlify build credits, we will use GitHub Pages for the initial levels.
	1. On GitHub.com, navigate to your repository's **Settings** tab.
	2. Click on **Pages** in the left-hand menu.
	3. Under **Build and deployment**, ensure "Deploy from a branch" is selected.
	4. Select your `main` branch and the `/ (root)` folder, then click **Save**.
	5. Your site will be live at `https://YOUR_USERNAME.github.io/Project-TV-Show/` (it may take a minute to appear).
	6. For a detailed walkthrough, follow the [Official CYF Deployment Guide](https://curriculum.codeyourfuture.io/guides/deploying/ghpages/).
	> [!TIP]
	> Deployment to **Netlify** is only required upon reaching **Level 500**. This helps conserve build credits during the development phase.
	Follow the [CYF GitHub Pages Deployment Guide](https://curriculum.codeyourfuture.io/guides/deploying/ghpages/).
	> [!TIP]
	> Deployment to **Netlify** is only required upon reaching **Level 500**. Using GitHub Pages until then helps conserve build credits during the development phase.

[illicitonion]

Suggested change

	> **Only proceed with this step once all the requirements above are fully functional and tested on your GitHub Pages site.** > This is your final "production" deployment.
	> **Only proceed with this step once all the requirements above are fully functional and tested on your GitHub Pages site.**
	> This is your final "production" deployment.

[illicitonion]

Suggested change

	To complete the project, we will move from GitHub Pages to **Netlify** to practice using a professional hosting platform.
	To complete the project, we will move from GitHub Pages to **Netlify** to practice using a more advanced hosting platform.

[illicitonion]

Suggested change

	1. **Log in:** Go to [app.netlify.com](https://app.netlify.com/) and log in with your GitHub account.
	2. **Add a new site:** Click on **"Add new site"** and select **"Import an existing project"**.
	3. **Connect GitHub:** Choose GitHub as your provider and select your `Project-TV-Show` repository.
	4. **Site Settings:** - Ensure the branch to deploy is `main`.
	- Leave "Build command" and "Publish directory" empty.
	- Click **"Deploy Project"**.
	5. **Customize URL:** - Go to **Site configuration** > **Site details** > **Change site name**.
	- Change it to: `cyf-USERNAME-tv.netlify.app` (replacing `USERNAME` with your GitHub username).
	For more details, refer to the [Official CYF Netlify Guide](https://curriculum.codeyourfuture.io/guides/deployment-netlify/).
	Follow the [Official CYF Netlify Deployment Guide](https://curriculum.codeyourfuture.io/guides/deployment-netlify/) for your project.