Update README.md

[Nitya-003]

Closes #355

Describe the add-ons or changes you've made 📃

This PR enhances the overall README documentation to improve onboarding and clarity for new contributors and first-time users.

Key improvements include:

• Added a clear Getting Started section with setup steps and prerequisites
• Introduced a Project Architecture overview explaining major modules like automation, authentication, admin tools, and AI models
• Included example use cases and commands to help users understand Jarvis functionality
• Improved contribution guidelines and PR expectations for open-source contributors (GSSoC, Hacktoberfest, IWOC, etc.)
• Fixed Markdown & HTML rendering issues to ensure badges and sections display correctly on GitHub

These changes make the repository more beginner-friendly and contributor-ready.

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Working Video 📷

Not applicable, as this PR focuses on documentation improvements only.

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Type of change ☑️

What sort of change have you made:

• Bug fix
• New feature
• Code style update (formatting, local variables)
• Documentation update
• Database update

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Note to reviewers 📄

This PR does not affect application logic or functionality.
All changes are documentation-only and aimed at improving contributor experience and readability.
Please review the README structure and content for clarity and completeness.

[github-actions]

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