Add Prettier configuration and formatting scripts

[Code-Paragon]

Problem

The repository lacks a standard Prettier configuration and script, making it difficult to enforce the clean code styles required for a large open-source project.

Expected behavior

A .prettierrc file is configured for standard Next/React development (e.g., single quotes, trailing commas) and a format script is added to package.json.

Files to update

• .prettierrc (create)
• package.json

Project relevance

Ensures uniform code formatting across all PRs, eliminating "style-only" diff noise during code reviews.

Acceptance criteria

• Feature works as described
• Tests are added or updated where needed
• Documentation is updated where needed
• npm run format successfully formats all files in the src directory
• No TypeScript, lint, test, or build errors