feat: add panic tracking and logging with PanicTracker

- Implemented PanicTracker to log panics using tracing within a dedicated span.
- Introduced PanicInfo struct to capture panic details.
- Added tests for panic catching and hook restoration.

feat: implement token-bucket rate limiter

- Created RateLimiter to manage token consumption with configurable rates and burst capacity.
- Added methods for acquiring tokens and checking available tokens.
- Included tests for rate limiting behavior and token availability.

feat: add automatic retry with exponential backoff

- Developed retry function to handle transient errors with configurable retry strategies.
- Introduced RetryConfig for customizing retry behavior and jitter.
- Added tests for various retry scenarios and error handling.

feat: implement graceful shutdown coordination

- Created ShutdownManager to manage shutdown signals and task completion.
- Introduced ShutdownSignal for tasks to observe shutdown requests.
- Added tests for shutdown request handling and task draining.

feat: add timeout functionality for async operations

- Implemented with_timeout function to enforce execution time limits on futures.
- Created Timeout struct for wrapping futures with a deadline.
- Added tests for timeout behavior and error mapping.

crates/corex-cache/Cargo.toml

@@ -0,0 +1,40 @@
+[package]
+name = "corex-cache"
+version = "0.1.0"
+edition = "2021"
+rust-version = "1.75"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/asepharyana/mytheclipse"
+homepage = "https://github.com/asepharyana/mytheclipse"
+documentation = "https://docs.rs/corex-cache"
+authors = ["asepharyana <superaseph@gmail.com>"]
+description = "Unified multi-layer cache abstraction: L1/L2 caching, cache-aside and auto-refresh, with pluggable backends."
+readme = "README.md"
+keywords = ["cache", "lru", "redis", "multilayer", "cache-aside"]
+categories = ["caching", "asynchronous"]
+
+[features]
+default = ["l1-memory", "cache-aside"]
+# L1 (in-process) backends.
+l1-memory = []
+l1-moka = ["l1-memory", "dep:moka"]
+# L2 (distributed) backends.
+l2-redis = ["l1-memory", "dep:redis"]
+# Cache-aside + auto-refresh helper.
+cache-aside = ["l1-memory", "dep:serde", "dep:serde_json"]
+
+[dependencies]
+tracing = "0.1"
+# Required unconditionally: the core `Cache` trait (always compiled) uses it.
+async-trait = "0.1"
+serde = { version = "1", features = ["derive"], optional = true }
+serde_json = { version = "1", optional = true }
+
+# L1: Moka (high-performance in-memory cache).
+moka = { version = "0.12", default-features = false, features = ["future"], optional = true }
+
+# L2: Redis/Valkey async client (multiplexed connection).
+redis = { version = "0.27", default-features = false, features = ["tokio-comp"], optional = true }
+
+[dev-dependencies]
+tokio = { version = "1.53", features = ["full"] }