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README.md

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-Creates or updates a .env file with specified environment variables and outputs its base64-encoded content.
+# 📝 Prepare Env File Action
+
+Effortlessly create or update your `.env` file and get its base64-encoded content ready for secure use in your workflows! 🚀🔐
+
+---
+
+## ✨ Features
+
+- 📄 **Automatic creation or updating** of your `.env` file.
+- 🔑 **Easily set or update environment variables** like `STACK_NAME`.
+- 📦 **Outputs base64-encoded content** for secure storage or transfer.
+- 📋 **Detailed debug logs** for easy troubleshooting.
+
+---
+
+## 📥 Inputs
+
+| Input          | Description                                   | Required |
+|----------------|-----------------------------------------------|----------|
+| `stack_name`   | The name of the stack to set in the `.env` file. | ✅ Yes   |
+
+---
+
+## 📤 Outputs
+
+| Output     | Description                                           | Example                      |
+|------------|-------------------------------------------------------|------------------------------|
+| `exists`   | Indicates if `.env` file existed before running action | `true` or `false`            |
+| `content`  | Base64-encoded content of the resulting `.env` file   | `U1RBQ0tfTkFNRT1teS1zdGFjaw==` |
+
+---
+
+## 🛠️ Example Usage
+
+Here's how you can integrate this action into your workflow:
+
+```yaml
+- name: Prepare .env File 📝
+  id: prepare-env
+  uses: your-org/prepare-env-file@main
+  with:
+    stack_name: my-awesome-stack
+
+- name: Use Encoded .env Content 🔐
+  run: |
+    echo "Encoded .env content: ${{ steps.prepare-env.outputs.content }}"
+```
+
+---
+
+## 🧑‍💻 How It Works
+
+This action performs the following steps:
+
+| Step | Description |
+|------|-------------|
+| 📄   | Checks if `.env` file exists; creates it if not. |
+| 🔄   | Adds or updates the `STACK_NAME` variable in `.env`. |
+| 📋   | Provides detailed debug logs showing all changes. |
+| 🔐   | Outputs the base64-encoded content of the final `.env` file. |
+
+---
+
+## 📖 Debugging & Logs
+
+Detailed debug logs are provided at every step, making troubleshooting easy:
+
+```
+DEBUG: .env file exists. Updating STACK_NAME.
+DEBUG: Updated existing STACK_NAME to 'my-awesome-stack'.
+DEBUG: Final .env content:
+STACK_NAME=my-awesome-stack
+DEBUG: Successfully encoded .env file to base64.
+```
+
+---
+
+## ⚠️ Requirements
+
+- Your workflow must have write permissions to the repository directory.
+- Bash shell environment.
+
+---
+
+## 📜 License
+
+This action is open-source software licensed under the MIT license.
+
+---
+
+Happy coding! 🎉
+
+— **Grand**
 
 ### Should probably use better alternatives like:
 - https://github.com/marketplace/actions/configuration-variable-substitution