feat: add NIST CSF 2.0 nist_csf field to all 754 cybersecurity skills

Mapped every skill to NIST CSF 2.0 subcategory IDs (GV/ID/PR/DE/RS/RC functions)
based on subdomain and content analysis. Restores 11 skills corrupted during
prior rebase, re-enriching with ATLAS, D3FEND, NIST AI RMF, and CSF 2.0 fields.

All 754 skills now carry structured mappings for all 5 security frameworks:
- MITRE ATT&CK (in tags)
- MITRE ATLAS v5.5 (atlas_techniques)
- MITRE D3FEND v1.3 (d3fend_techniques)
- NIST AI RMF 1.0 (nist_ai_rmf)
- NIST CSF 2.0 (nist_csf)

skills/analyzing-ethereum-smart-contract-vulnerabilities/SKILL.md

@@ -1,12 +1,25 @@
 ---
 name: analyzing-ethereum-smart-contract-vulnerabilities
-description: Perform static and symbolic analysis of Solidity smart contracts using Slither and Mythril to detect reentrancy, integer overflow, access control, and other vulnerability classes before deployment to Ethereum mainnet.
+description: Perform static and symbolic analysis of Solidity smart contracts using Slither and Mythril to detect reentrancy,
+  integer overflow, access control, and other vulnerability classes before deployment to Ethereum mainnet.
 domain: cybersecurity
 subdomain: blockchain-security
-tags: [ethereum, solidity, smart-contract, slither, mythril, blockchain, defi, audit]
-version: "1.0"
+tags:
+- ethereum
+- solidity
+- smart-contract
+- slither
+- mythril
+- blockchain
+- defi
+- audit
+version: '1.0'
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- PR.DS-01
+- PR.DS-02
+- ID.RA-01
 ---
 
 # Analyzing Ethereum Smart Contract Vulnerabilities