Refactor job client into separate crate

- Moved client code from rust/src/client.rs to rust/client/ subdirectory
- Created separate hero-job-client crate for better modularity
- Updated Cargo.toml to include client as workspace member
- Client can now be used independently of the main hero-job crate

rust/client/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "hero-job-client"
+version = "0.1.0"
+edition = "2021"
+description = "Redis client for Hero job management"
+
+[dependencies]
+hero-job = { path = ".." }
+redis = { version = "0.25", features = ["aio", "tokio-comp"] }
+tokio = { version = "1.0", features = ["rt", "time"] }
+chrono = { version = "0.4", features = ["serde"] }
+serde_json = "1.0"
+thiserror = "1.0"
+log = "0.4"
+
+[lib]
+name = "hero_job_client"
+path = "src/lib.rs"