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/detecting-stuxnet-style-attacks/SKILL.md

@@ -1,18 +1,30 @@
 ---
 name: detecting-stuxnet-style-attacks
-description: >
-  This skill covers detecting sophisticated cyber-physical attacks that follow the
-  Stuxnet attack pattern of modifying PLC logic while spoofing sensor readings to
-  hide the manipulation from operators. It addresses PLC logic integrity monitoring,
-  physics-based process anomaly detection, engineering workstation compromise indicators,
-  USB-borne attack vectors, and multi-stage attack chain detection spanning IT-to-OT
-  lateral movement through to process manipulation.
+description: 'This skill covers detecting sophisticated cyber-physical attacks that follow the Stuxnet attack pattern of modifying
+  PLC logic while spoofing sensor readings to hide the manipulation from operators. It addresses PLC logic integrity monitoring,
+  physics-based process anomaly detection, engineering workstation compromise indicators, USB-borne attack vectors, and multi-stage
+  attack chain detection spanning IT-to-OT lateral movement through to process manipulation.
+
+  '
 domain: cybersecurity
 subdomain: ot-ics-security
-tags: [ot-security, ics, scada, industrial-control, iec62443, stuxnet, plc-integrity, apt]
+tags:
+- ot-security
+- ics
+- scada
+- industrial-control
+- iec62443
+- stuxnet
+- plc-integrity
+- apt
 version: 1.0.0
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- PR.IR-01
+- DE.CM-01
+- ID.AM-05
+- GV.OC-02
 ---
 
 # Detecting Stuxnet-Style Attacks