feat: Add CI/CD workflows for testing and publishing SAL crates

- Add a workflow for testing the publishing setup
- Add a workflow for publishing SAL crates to crates.io
- Improve crate metadata and version management
- Add optional dependencies for modularity
- Improve documentation for publishing and usage

Cargo.toml

@@ -87,16 +87,58 @@ urlencoding = "2.1.3"
 tokio-test = "0.4.4"
 
 [dependencies]
-thiserror = "2.0.12"                             # For error handling in the main Error enum
-sal-git = { path = "git" }
-sal-redisclient = { path = "redisclient" }
-sal-mycelium = { path = "mycelium" }
-sal-text = { path = "text" }
-sal-os = { path = "os" }
-sal-net = { path = "net" }
-sal-zinit-client = { path = "zinit_client" }
-sal-process = { path = "process" }
-sal-virt = { path = "virt" }
-sal-postgresclient = { path = "postgresclient" }
-sal-vault = { path = "vault" }
-sal-rhai = { path = "rhai" }
+thiserror = "2.0.12" # For error handling in the main Error enum
+
+# Optional dependencies - users can choose which modules to include
+sal-git = { path = "git", optional = true }
+sal-kubernetes = { path = "kubernetes", optional = true }
+sal-redisclient = { path = "redisclient", optional = true }
+sal-mycelium = { path = "mycelium", optional = true }
+sal-text = { path = "text", optional = true }
+sal-os = { path = "os", optional = true }
+sal-net = { path = "net", optional = true }
+sal-zinit-client = { path = "zinit_client", optional = true }
+sal-process = { path = "process", optional = true }
+sal-virt = { path = "virt", optional = true }
+sal-postgresclient = { path = "postgresclient", optional = true }
+sal-vault = { path = "vault", optional = true }
+sal-rhai = { path = "rhai", optional = true }
+
+[features]
+default = []
+
+# Individual module features
+git = ["dep:sal-git"]
+kubernetes = ["dep:sal-kubernetes"]
+redisclient = ["dep:sal-redisclient"]
+mycelium = ["dep:sal-mycelium"]
+text = ["dep:sal-text"]
+os = ["dep:sal-os"]
+net = ["dep:sal-net"]
+zinit_client = ["dep:sal-zinit-client"]
+process = ["dep:sal-process"]
+virt = ["dep:sal-virt"]
+postgresclient = ["dep:sal-postgresclient"]
+vault = ["dep:sal-vault"]
+rhai = ["dep:sal-rhai"]
+
+# Convenience feature groups
+core = ["os", "process", "text", "net"]
+clients = ["redisclient", "postgresclient", "zinit_client", "mycelium"]
+infrastructure = ["git", "vault", "kubernetes", "virt"]
+scripting = ["rhai"]
+all = [
+    "git",
+    "kubernetes",
+    "redisclient",
+    "mycelium",
+    "text",
+    "os",
+    "net",
+    "zinit_client",
+    "process",
+    "virt",
+    "postgresclient",
+    "vault",
+    "rhai",
+]