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/conducting-post-incident-lessons-learned/SKILL.md

@@ -1,13 +1,27 @@
 ---
 name: conducting-post-incident-lessons-learned
-description: Facilitate structured post-incident reviews to identify root causes, document what worked and failed, and produce actionable recommendations to improve future incident response.
+description: Facilitate structured post-incident reviews to identify root causes, document what worked and failed, and produce
+  actionable recommendations to improve future incident response.
 domain: cybersecurity
 subdomain: incident-response
-tags: [incident-response, lessons-learned, post-incident, after-action-review, process-improvement]
-mitre_attack: ["T1190", "T1566", "T1078"]
-version: "1.0"
+tags:
+- incident-response
+- lessons-learned
+- post-incident
+- after-action-review
+- process-improvement
+mitre_attack:
+- T1190
+- T1566
+- T1078
+version: '1.0'
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- RS.MA-01
+- RS.MA-02
+- RS.AN-03
+- RC.RP-01
 ---
 
 # Conducting Post-Incident Lessons Learned