refactor: update README for clarity and consistency in messaging

[AnkanSaha]

This pull request significantly rewrites and restructures the README.md to better communicate EdgeBalancer’s value proposition, simplify onboarding, and clarify pricing and features. The changes focus on making the product easier to understand for new users, highlighting its advantages over traditional solutions, and providing clear instructions and comparisons.

Major improvements in messaging and structure:

• Replaces the problem/solution framing with a benefits-focused introduction, emphasizing simplicity, cost savings, and ease of use.
• Adds a live demo link and a clear, step-by-step “How it works” and “Quick start” section for new users.
• Refines the explanation of routing strategies, health checks, security features, and the AI assistant, making features more discoverable and concise.

Pricing and cost comparison:

• Introduces a detailed pricing table for different plans, including free, trial, student, and pro options, with annual discounts and feature breakdowns.
• Adds a direct cost comparison table versus AWS ALB and Cloudflare Load Balancing, with example traffic tiers and pricing.

Documentation and navigation:

• Updates and simplifies the links section, removing redundant links and focusing on website, pricing, and contact.