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/performing-firmware-malware-analysis/SKILL.md

@@ -1,17 +1,27 @@
 ---
 name: performing-firmware-malware-analysis
-description: >
-  Analyzes firmware images for embedded malware, backdoors, and unauthorized modifications
-  targeting routers, IoT devices, UEFI/BIOS, and embedded systems. Covers firmware extraction,
-  filesystem analysis, binary reverse engineering, and bootkit detection. Activates for
-  requests involving firmware security analysis, IoT malware investigation, UEFI rootkit
+description: 'Analyzes firmware images for embedded malware, backdoors, and unauthorized modifications targeting routers,
+  IoT devices, UEFI/BIOS, and embedded systems. Covers firmware extraction, filesystem analysis, binary reverse engineering,
+  and bootkit detection. Activates for requests involving firmware security analysis, IoT malware investigation, UEFI rootkit
   detection, or embedded device compromise assessment.
+
+  '
 domain: cybersecurity
 subdomain: malware-analysis
-tags: [malware, firmware, IoT, UEFI, embedded-security]
+tags:
+- malware
+- firmware
+- IoT
+- UEFI
+- embedded-security
 version: 1.0.0
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- DE.AE-02
+- RS.AN-03
+- ID.RA-01
+- DE.CM-01
 ---
 
 # Performing Firmware Malware Analysis