[WIP] version 2

[evangwt]

This pull request refactors the grc GORM cache plugin to use a clean, abstract cache interface and removes the direct dependency on go-redis. The documentation and examples are updated to reflect a backend-agnostic, pluggable architecture. Tests and example code now use SQLite and in-memory cache by default, making the project easier to use and test without external dependencies.

Major architectural changes:

• The cache backend is now defined by a simple CacheClient interface, allowing users to implement any storage backend (memory, Redis, Memcached, file, etc.) and switch backends without changing application code. (README.md, cache.go) [1] [2]

• All direct usage of go-redis and related code has been removed from the core library and tests. Redis support is now optional via a separate, simple client implementation. (cache.go, cache_test.go, example/main.go) [1] [2] [3]

Documentation and examples:

• The README.md is rewritten to highlight the new architecture, usage patterns, cache control, available implementations, migration guide, and contribution instructions. (README.md)

• Example code now uses SQLite and MemoryCache for demonstration, with Redis usage shown as an optional, commented-out section. (example/main.go, example/memory_example.go) [1] [2] [3]

Testing improvements:

• Tests now use an in-memory cache implementation and skip execution if required environment variables for the database are missing, improving portability and reliability. (cache_test.go) [1] [2]

Error handling and API consistency:

• Introduced a standard ErrCacheMiss error for cache misses, replacing backend-specific error handling. (cache.go) [1] [2]