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/securing-aws-lambda-execution-roles/SKILL.md

@@ -1,15 +1,27 @@
 ---
 name: securing-aws-lambda-execution-roles
-description: >
-  Securing AWS Lambda execution roles by implementing least-privilege IAM policies,
-  applying permission boundaries, restricting resource-based policies, using IAM Access
-  Analyzer to validate permissions, and enforcing role scoping through SCPs.
+description: 'Securing AWS Lambda execution roles by implementing least-privilege IAM policies, applying permission boundaries,
+  restricting resource-based policies, using IAM Access Analyzer to validate permissions, and enforcing role scoping through
+  SCPs.
+
+  '
 domain: cybersecurity
 subdomain: cloud-security
-tags: [cloud-security, aws, lambda, iam, least-privilege, execution-roles]
-version: "1.0"
+tags:
+- cloud-security
+- aws
+- lambda
+- iam
+- least-privilege
+- execution-roles
+version: '1.0'
 author: mahipal
 license: Apache-2.0
+nist_csf:
+- PR.IR-01
+- ID.AM-08
+- GV.SC-06
+- DE.CM-01
 ---
 
 # Securing AWS Lambda Execution Roles