feat: Initialize Prettier and ESLint with formatting workflows

[Yashh56]

This pull request introduces several improvements focused on project automation, code style enforcement, and documentation clarity. The main changes are the addition of GitHub Actions workflows for linting and formatting, the introduction of Prettier configuration and ignore files, and significant enhancements to the project's architecture and decision records.

Automation and Code Quality

• Added a GitHub Actions workflow for linting (.github/workflows/lint.yml), which runs on pull requests targeting master or develop and checks code quality using pnpm lint.
• Added a GitHub Actions workflow for code formatting (.github/workflows/format.yml), ensuring consistent code style by running pnpm format:check on relevant file changes.
• Introduced .prettierrc.json and .prettierignore to define and enforce Prettier formatting rules and specify files/directories to ignore. [1] [2]

Documentation Improvements

• Major updates to ARCHITECTURE.md, including clearer explanations of the architecture layers, data flow, feature organization, and testing strategy. The formatting was improved for readability, and step-by-step checklists were added for feature development and testing. [1] [2] [3] [4] [5] [6]
• Enhanced DECISIONS.md with additional context and improved formatting for architectural decisions, making trade-offs and motivations clearer.

Minor Documentation Updates

• Added clarifications and improved formatting in AGENTS.md and CLAUDE.md for better onboarding and development guidance. [1] [2] [3] [4] [5]

These changes collectively strengthen code consistency, automate quality checks, and make the project's structure and rationale more accessible to contributors.