Extract and generalize caching framework from studio-mcp

[avrabe]

Summary

Extract the sophisticated caching implementation from studio-mcp and create a generalized pulseengine-mcp-cache crate that can be used across different MCP server implementations.

Background

Studio-MCP implements a highly optimized caching system that reduces API calls by ~80% with features including:

• Multi-layer intelligent caching with smart invalidation
• Performance monitoring and health metrics
• Sensitive data filtering
• Configurable TTL policies and memory management
• Multi-tenant support

Key components to extract:

• plm_cache.rs (45KB) - Core PLM-specific cache implementation
• invalidation_service.rs (17KB) - Smart cache invalidation logic
• sensitive_filter.rs (16KB) - Security filtering for cached data
• mod.rs (30KB) - Main cache coordination and interfaces

Implementation Tasks

Core Cache Infrastructure

• Create new pulseengine-mcp-cache crate in workspace
• Extract core cache storage and TTL management from studio-mcp
• Implement trait-based abstractions for domain-specific behaviors
• Port performance monitoring and health metrics system

Trait-Based Abstractions

• CacheTypeDetector trait for domain-specific type detection
• InvalidationRuleProvider trait for operation-based invalidation
• SensitiveDataFilter trait for security filtering
• ResourceKeyGenerator trait for key generation patterns
• CacheMetrics trait for performance monitoring

Configuration System

• Environment-aware configuration (dev/staging/prod)
• Configurable TTL policies per cache type
• Memory limits and eviction thresholds
• Sensitive data patterns and field definitions
• Multi-tenant isolation settings

WASM Compatibility

• Replace tokio-specific primitives with async trait abstractions
• Use feature flags for runtime selection (tokio vs wasm-compatible)
• Implement WASM-compatible time and memory APIs
• Add browser-compatible version using web-sys

Integration Points

• Cache context middleware for MCP requests
• Automatic cache invalidation hooks for write operations
• Performance metrics endpoints integration
• Health check integration with MCP server framework

Acceptance Criteria

• New pulseengine-mcp-cache crate compiles for both native and WASM targets
• Trait-based design allows easy customization for different domains
• Performance comparable to original studio-mcp implementation
• Comprehensive documentation and usage examples
• Integration examples with existing MCP servers
• Full test coverage including performance benchmarks

Related Issues

• WASM32-WASIP2 Target Support (Add WASM32-WASIP2 target support for WebAssembly deployment #26)
• Storage Backend Abstraction (#TBD)
• Performance Monitoring Framework (#TBD)

References

• studio-mcp cache implementation
• Original performance benchmarks and metrics