Update README repository url and setup instructions

The git repository URL in README has been updated to the correct one as previous URL was not accessible. Also, an additional step has been added for setup procedure to configure the OPENAI_API_KEY. This is essential for the application to function properly and hence was included in the instructions.

README.md

@@ -44,14 +44,18 @@
 
 1. Clone the repository
    ```sh
-   git clone https://github.com/supernova3339/ai-problem-solver.git
+   git clone https://github.com/supernova3339/aiproblemsolver.git
    ```
 2. Install dependencies
    ```sh
    cd ai-problem-solver
    npm install
    ```
-3. Start the development server
+3. Configure the application
+   ```sh
+   echo "OPENAI_API_KEY" > .env.local
+   ```
+4. Start the development server
    ```sh
    npm run dev
    ```