[DOCS] Improve README to align with Hiero standards and act as documentation hub

[danielmarv]

Description

The current README provides a basic overview of the project but does not fully align with Hiero repository standards or reflect the current Next.js-based architecture.

Additionally, most detailed documentation already exists in the /docs directory. The README should not duplicate this content, but instead act as a central entry point (hub) that guides users and contributors to the appropriate documentation.

This issue focuses on restructuring the README to be clear, concise, and serve as the primary navigation layer for the repository.

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Problem

• The README does not fully reflect the current Next.js architecture
• It does not clearly guide users to the /docs directory
• Some information is either missing or not well structured
• There is no clear separation between overview vs detailed documentation
• Risk of duplicating documentation that already exists in /docs

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Goal

Create a README that:

• acts as a central documentation hub
• provides a clear high-level overview of the project
• links to detailed documentation in /docs
• aligns with Hiero documentation standards
• improves onboarding for new contributors

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Scope of Work

• Restructure the README into a clean, scannable format
• Add a strong project overview and purpose section
• Document the tech stack at a high level
• Improve “Getting Started” instructions
• Add a Documentation section linking to /docs content
• Avoid duplicating detailed documentation already in /docs
• Provide clear navigation for:
  • contributors
  • developers
  • maintainers
• Remove outdated references (e.g., Hugo-specific concepts)
• Ensure consistent tone and formatting

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Proposed Approach

The README should:

• Summarize, not duplicate
• Link out, not expand excessively

Example structure:

• Overview
• Tech Stack
• Getting Started
• Project Structure (high-level)
• Documentation (links to /docs)
• Contributing
• License

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Expected Outcome

• README becomes the entry point to the repository
• /docs becomes the source of detailed documentation
• Clear separation between overview and deep documentation
• Improved developer and contributor onboarding experience

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Acceptance Criteria

• README is concise and well-structured
• README links clearly to relevant /docs files
• No unnecessary duplication of documentation content
• Setup instructions are accurate and minimal
• Documentation navigation is clear and intuitive
• No outdated (Hugo-era) references remain
• README aligns with Hiero repository standards

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Additional Context

The /docs directory already contains detailed documentation and should remain the primary location for in-depth guides. The README should complement this by acting as a navigation and onboarding layer rather than a full documentation source.