[Skills Router] Local Cache + Guardrails

[fentz26]

Summary

Implement local guardrails for the Skills Router including L1/L2 caching and local policy enforcement.

Parent Epic

• 🧭 Epic: Skills Router (Cross-Repo) #82

Note

Distributed cache (L3) and cloud guardrails are handled in Neona-Cloud.

Components

Local Cache System

• L1 Cache: In-memory LRU cache (fast, limited size)
• L2 Cache: Persistent cache (SQLite)

Local Guardrails

• Safety Checks: Block dangerous skills locally
• Permission Checks: User-based skill access control
• Policy Checks: Integration with local policy engine
• Rate Limiting: Local rate limits

Implementation

Files to Create/Modify

• internal/registry/skill/router/cache.go
• internal/registry/skill/router/guardrails.go

Configuration

skills_router:
  cache:
    l1_size: 1000
    l1_ttl: 5m
    l2_ttl: 1h
  guardrails:
    enable_safety_checks: true
    enable_rate_limiting: true
    enable_policy_checks: true
    max_results: 10

Acceptance Criteria

• L1 in-memory cache works
• L2 SQLite cache works
• Cache cascading (L1 → L2)
• Cache expiration works
• Safety guard blocks inappropriate skills
• Local rate limiting works
• Policy engine integration

Related Issues

• Neona-Cloud#20 - Distributed Cache (L3)
• Neona-Cloud#21 - Cloud Guardrails