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/implementing-container-image-minimal-base-with-distroless/SKILL.md

@@ -1,12 +1,26 @@
 ---
 name: implementing-container-image-minimal-base-with-distroless
-description: Reduce container attack surface by building application images on Google distroless base images that contain only the application runtime with no shell, package manager, or unnecessary OS utilities.
+description: Reduce container attack surface by building application images on Google distroless base images that contain
+  only the application runtime with no shell, package manager, or unnecessary OS utilities.
 domain: cybersecurity
 subdomain: container-security
-tags: [distroless, container-images, minimal-base, attack-surface, docker, security-hardening, supply-chain, kubernetes]
-version: "1.0"
+tags:
+- distroless
+- container-images
+- minimal-base
+- attack-surface
+- docker
+- security-hardening
+- supply-chain
+- kubernetes
+version: '1.0'
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- PR.PS-01
+- PR.IR-01
+- ID.AM-08
+- DE.CM-01
 ---
 
 # Implementing Container Image Minimal Base with Distroless