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-rootkit-activity/SKILL.md

@@ -1,17 +1,27 @@
 ---
 name: detecting-rootkit-activity
-description: >
-  Detects rootkit presence on compromised systems by identifying hidden processes, hooked
-  system calls, modified kernel structures, hidden files, and covert network connections
-  using memory forensics, cross-view detection, and integrity checking techniques.
-  Activates for requests involving rootkit detection, hidden process discovery, kernel
-  integrity checking, or system call hook analysis.
+description: 'Detects rootkit presence on compromised systems by identifying hidden processes, hooked system calls, modified
+  kernel structures, hidden files, and covert network connections using memory forensics, cross-view detection, and integrity
+  checking techniques. Activates for requests involving rootkit detection, hidden process discovery, kernel integrity checking,
+  or system call hook analysis.
+
+  '
 domain: cybersecurity
 subdomain: malware-analysis
-tags: [malware, rootkit, detection, kernel-analysis, memory-forensics]
+tags:
+- malware
+- rootkit
+- detection
+- kernel-analysis
+- memory-forensics
 version: 1.0.0
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- DE.AE-02
+- RS.AN-03
+- ID.RA-01
+- DE.CM-01
 ---
 
 # Detecting Rootkit Activity