feat: Refactor sentiment handling and enhance processing logic for session data

TODO.md

@@ -1,5 +1,78 @@
 # TODO.md
 
+# Refactor!!!
+
+> Based on my analysis of the codebase, here is a plan with recommendations for improving the project. The focus is on enhancing standardization, abstraction, user experience, and visual
+  design.
+
+## High-Level Recommendations
+
+The project has a solid foundation, but it could be significantly improved by focusing on three key areas:
+
+1. Adopt a UI Component Library: While Tailwind CSS is excellent for styling, using a component library like ShadCN/UI or Headless UI would provide pre-built, accessible, and visually
+   consistent components, saving development time and improving the user experience.
+2. Refactor for Next.js App Router: The project currently uses a mix of the pages and app directories. Migrating fully to the App Router would simplify the project structure, improve
+   performance, and align with the latest Next.js features.
+3. Enhance User Experience: Implementing consistent loading and error states, improving responsiveness, and providing better user feedback would make the application more robust and
+   user-friendly.
+
+## Detailed Improvement Plan
+
+Here is a phased plan to implement these recommendations:
+
+### Phase 1: Foundational Improvements (Standardization & Abstraction)
+
+This phase focuses on cleaning up the codebase, standardizing the project structure, and improving the abstraction of core functionalities.
+
+1. Standardize Project Structure:
+   * Unify Server File: Consolidate server.js, server.mjs, and server.ts into a single server.ts file to remove redundancy.
+   * Migrate to App Router: Move all routes from the pages/api directory to the app/api directory. This will centralize routing logic within the app directory.
+   * Standardize Naming Conventions: Ensure all files and components follow a consistent naming convention (e.g., PascalCase for components, kebab-case for files).
+
+2. Introduce a UI Component Library:
+   * Integrate ShadCN/UI: Add ShadCN/UI to the project to leverage its extensive library of accessible and customizable components.
+   * Replace Custom Components: Gradually replace custom-built components in the components/ directory with their ShadCN/UI equivalents. This will improve visual consistency and reduce
+     maintenance overhead.
+
+3. Refactor Core Logic:
+   * Centralize Data Fetching: Create a dedicated module (e.g., lib/data-service.ts) to handle all data fetching logic, abstracting away the details of using Prisma and external APIs.
+   * Isolate Business Logic: Ensure that business logic (e.g., session processing, metric calculation) is separated from the API routes and UI components.
+
+### Phase 2: UX and Visual Enhancements
+
+This phase focuses on improving the user-facing aspects of the application.
+
+1. Implement Comprehensive Loading and Error States:
+   * Skeleton Loaders: Use skeleton loaders for dashboard components to provide a better loading experience.
+   * Global Error Handling: Implement a global error handling strategy to catch and display user-friendly error messages for API failures or other unexpected issues.
+
+2. Redesign the Dashboard:
+   * Improve Information Hierarchy: Reorganize the dashboard to present the most important information first.
+   * Enhance Visual Appeal: Use the new component library to create a more modern and visually appealing design with a consistent color palette and typography.
+   * Improve Chart Interactivity: Add features like tooltips, zooming, and filtering to the charts to make them more interactive and informative.
+
+3. Ensure Full Responsiveness:
+   * Mobile-First Approach: Review and update all pages and components to ensure they are fully responsive and usable on a wide range of devices.
+
+### Phase 3: Advanced Topics (Security, Performance, and Documentation)
+
+This phase focuses on long-term improvements to the project's stability, performance, and maintainability.
+
+1. Conduct a Security Review:
+   * Input Validation: Ensure that all user inputs are properly validated on both the client and server sides.
+   * Dependency Audit: Regularly audit dependencies for known vulnerabilities.
+
+2. Optimize Performance:
+   * Code Splitting: Leverage Next.js's automatic code splitting to reduce initial load times.
+   * Caching: Implement caching strategies for frequently accessed data to reduce database load and improve API response times.
+
+3. Expand Documentation:
+   * API Documentation: Create detailed documentation for all API endpoints.
+   * Component Library: Document the usage and props of all reusable components.
+   * Update `AGENTS.md`: Keep the AGENTS.md file up-to-date with any architectural changes.
+
+Would you like me to start implementing any part of this plan? I would suggest starting with Phase 1 to build a solid foundation for the other improvements.
+
 ## Dashboard Integration
 
 - [ ] **Resolve `GeographicMap.tsx` and `ResponseTimeDistribution.tsx` data simulation**