Fix Broken Links and Standardize Formatting in README.md

[fs0ci5ty]

This PR improves the quality and maintainability of the curated AI resources list.

Key changes:

• Link Verification and Updates: All 200+ links were checked. Broken links were either updated to their new locations (e.g., OEIS, Scipy, Maxima) or replaced with current resources.
• Standardized Formatting: Standardized all resource entries to the - [Resource Name](URL) Markdown format for better readability and consistency.
• Specific Course Links: Restored specific URLs for various learning paths from Kaggle, Microsoft, and EdX that were previously generic or broken.
• Heading Standardization: Ensured all category and sub-category headings use consistent Markdown levels.
• Security Upgrades: Upgraded legacy HTTP links to HTTPS where the target sites supported it.

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PR created automatically by Jules for task 15828293723067355557 started by @fs0ci5ty

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