feat: add Agent Skills and restructure documentation

- Add 47 Agent Skills across 14 plugins following Anthropic's specification
  - Python (5): async patterns, testing, packaging, performance, UV package manager
  - JavaScript/TypeScript (4): advanced types, Node.js patterns, testing, modern JS
  - Kubernetes (4): manifests, Helm charts, GitOps, security policies
  - Cloud Infrastructure (4): Terraform, multi-cloud, hybrid networking, cost optimization
  - CI/CD (4): pipeline design, GitHub Actions, GitLab CI, secrets management
  - Backend (3): API design, architecture patterns, microservices
  - LLM Applications (4): LangChain, prompt engineering, RAG, evaluation
  - Blockchain/Web3 (4): DeFi protocols, NFT standards, Solidity security, Web3 testing
  - Framework Migration (4): React, Angular, database, dependency upgrades
  - Observability (4): Prometheus, Grafana, distributed tracing, SLO
  - Payment Processing (4): Stripe, PayPal, PCI compliance, billing
  - API Scaffolding (1): FastAPI templates
  - ML Operations (1): ML pipeline workflow
  - Security (1): SAST configuration

- Restructure documentation into /docs directory
  - agent-skills.md: Complete guide to all 47 skills
  - agents.md: All 85 agents with model configuration
  - plugins.md: Complete catalog of 63 plugins
  - usage.md: Commands, workflows, and best practices
  - architecture.md: Design principles and patterns

- Update README.md
  - Add Agent Skills banner announcement
  - Reduce length by ~75% with links to detailed docs
  - Add What's New section showcasing Agent Skills
  - Add Popular Use Cases with real examples
  - Improve navigation with Core Guides and Quick Links

- Update marketplace.json with skills arrays for 14 plugins

All 47 skills follow Agent Skills Specification:
- Required YAML frontmatter (name, description)
- Use when activation clauses
- Progressive disclosure architecture
- Under 1024 character descriptions

plugins/cloud-infrastructure/skills/terraform-module-library/references/aws-modules.md

@@ -0,0 +1,63 @@
+# AWS Terraform Module Patterns
+
+## VPC Module
+- VPC with public/private subnets
+- Internet Gateway and NAT Gateways
+- Route tables and associations
+- Network ACLs
+- VPC Flow Logs
+
+## EKS Module
+- EKS cluster with managed node groups
+- IRSA (IAM Roles for Service Accounts)
+- Cluster autoscaler
+- VPC CNI configuration
+- Cluster logging
+
+## RDS Module
+- RDS instance or cluster
+- Automated backups
+- Read replicas
+- Parameter groups
+- Subnet groups
+- Security groups
+
+## S3 Module
+- S3 bucket with versioning
+- Encryption at rest
+- Bucket policies
+- Lifecycle rules
+- Replication configuration
+
+## ALB Module
+- Application Load Balancer
+- Target groups
+- Listener rules
+- SSL/TLS certificates
+- Access logs
+
+## Lambda Module
+- Lambda function
+- IAM execution role
+- CloudWatch Logs
+- Environment variables
+- VPC configuration (optional)
+
+## Security Group Module
+- Reusable security group rules
+- Ingress/egress rules
+- Dynamic rule creation
+- Rule descriptions
+
+## Best Practices
+
+1. Use AWS provider version ~> 5.0
+2. Enable encryption by default
+3. Use least-privilege IAM
+4. Tag all resources consistently
+5. Enable logging and monitoring
+6. Use KMS for encryption
+7. Implement backup strategies
+8. Use PrivateLink when possible
+9. Enable GuardDuty/SecurityHub
+10. Follow AWS Well-Architected Framework