This pull request introduces significant updates to the database integration and development environment for the project, primarily targeting an upgrade to Prisma 7 and the adoption of the Better SQLite3 adapter. The changes also improve environment variable management, update dependencies, and document architectural and development patterns for contributors.

Database Integration and Prisma Upgrade:

• Upgraded Prisma and @prisma/client to version 7.1.0, and switched to using @prisma/adapter-better-sqlite3 for improved SQLite support. [1] [2]
• Added a new prisma.config.ts file to define Prisma configuration, including dynamic database URL loading from environment variables.
• Refactored the Prisma client singleton in db.client.ts to use the Better SQLite3 adapter and to require the DATABASE_URL environment variable, improving error handling and configuration flexibility.

Environment Variable and Docker Improvements:

• Updated the Dockerfile to Node 22, added environment variables for database configuration, and ensured compatibility with Prisma 7 and the new adapter. [1] [2] [3]
• Added .devcontainer/devcontainer.env_example with example environment variables to streamline local development setup.

Documentation and Developer Experience:

• Introduced a comprehensive architecture and coding instructions document in .github/copilot-instructions.md to guide contributors on project structure, patterns, and best practices.

Dependency Management:

• Moved several type dependencies from dependencies to devDependencies in package.json and added new type definitions for Better SQLite3, clarifying runtime vs. development requirements. [1] [2]
• Added dotenv to dependencies to ensure environment variables are loaded consistently across the codebase.

Prisma Schema and Codebase Clean-up:

• Updated prisma/schema.prisma to remove the hardcoded database URL, making configuration fully environment-driven and ready for Prisma 7 features. [1] [2]
• Minor code clean-up in imports for Prisma runtime types to align with the new version. [1] [2]