feat: Add service manager support

- Add a new service manager crate for dynamic service management
- Integrate service manager with Rhai for scripting
- Provide examples for circle worker management and basic usage
- Add comprehensive tests for service lifecycle and error handling
- Implement cross-platform support for macOS and Linux (zinit/systemd)

service_manager/Cargo.toml

@@ -2,21 +2,41 @@
 name = "sal-service-manager"
 version = "0.1.0"
 edition = "2021"
+authors = ["PlanetFirst <info@incubaid.com>"]
+description = "SAL Service Manager - Cross-platform service management for dynamic worker deployment"
+repository = "https://git.threefold.info/herocode/sal"
+license = "Apache-2.0"
 
 [dependencies]
-async-trait = "0.1"
+# Use workspace dependencies for consistency
 thiserror = "1.0"
 tokio = { workspace = true }
 log = { workspace = true }
 serde = { workspace = true }
-serde_json = { workspace = true, optional = true }
+serde_json = { workspace = true }
+futures = { workspace = true }
+once_cell = { workspace = true }
+# Use base zinit-client instead of SAL wrapper
+zinit-client = { version = "0.3.0" }
+# Optional Rhai integration
+rhai = { workspace = true, optional = true }
 
-zinit_client = { package = "sal-zinit-client", path = "../zinit_client", optional = true }
 
 [target.'cfg(target_os = "macos")'.dependencies]
 # macOS-specific dependencies for launchctl
 plist = "1.6"
 
 [features]
-default = []
-zinit = ["dep:zinit_client", "dep:serde_json"]
+default = ["zinit"]
+zinit = []
+rhai = ["dep:rhai"]
+
+# Enable zinit feature for tests
+[dev-dependencies]
+tokio-test = "0.4"
+rhai = { workspace = true }
+tempfile = { workspace = true }
+
+[[test]]
+name = "zinit_integration_tests"
+required-features = ["zinit"]