Add PR template for cookbook contributions

Author: james-pplx

.github/PULL_REQUEST_TEMPLATE/pull_request_template.md

@@ -0,0 +1,32 @@
+# Cookbook Project Contribution
+
+## Project Overview
+<!-- Provide a concise description of what your project does and the problem it solves -->
+
+## API Integration
+<!-- Describe how your project uses the Perplexity API, including which models and features are leveraged -->
+
+## Impact & Value
+<!-- Explain why this project is valuable to the developer community and how it showcases the API's capabilities -->
+
+## Technical Implementation
+<!-- Briefly describe the technical approach and any notable implementation details -->
+
+## Setup & Dependencies
+<!-- List any dependencies, environment requirements, or setup steps needed -->
+
+## Screenshots/Demo
+<!-- If applicable, include screenshots, demo links, or example outputs -->
+
+## Checklist
+<!-- Mark the following with an 'x' like [x] -->
+
+- [ ] Project is fully functional with no major bugs
+- [ ] Code includes proper error handling
+- [ ] Documentation is complete (README, code comments, etc.)
+- [ ] All credentials/API keys have been removed
+- [ ] Code follows best practices for the language/framework used
+- [ ] Project demonstrates a unique or valuable use case
+
+## Additional Notes
+<!-- Any other information that might be helpful for reviewers -->