feat: add blockchain resource

[sg-milad]

Added two high-quality blockchain development learning resources:

• Cyfrin: Known for audit-focused courses like the Foundry bootcamp, Solidity examples, and in-depth Web3 tutorials.
• RareSkills: Offers advanced topics including smart contract security, zero-knowledge proofs, and MEV with bootcamp-style learning.
  they are free
  Both are widely used and respected in the Ethereum development community and add strong practical and theoretical value for aspiring blockchain engineers.

[Sudouble]

来件已收到，我会尽快处理！

[iOSMaL]

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