feat: Add sal-net package to workspace

- Add new sal-net package to the workspace.
- Update MONOREPO_CONVERSION_PLAN.md to reflect the
  addition of the sal-net package and mark it as
  production-ready.
- Add Cargo.toml and README.md for the sal-net package.

net/tests/ssh_tests.rs

@@ -0,0 +1,285 @@
+use sal_net::SshConnectionBuilder;
+use std::path::PathBuf;
+use std::time::Duration;
+
+#[tokio::test]
+async fn test_ssh_connection_builder_new() {
+    // Test that builder creates a functional connection with defaults
+    let connection = SshConnectionBuilder::new().build();
+
+    // Test that the connection can actually attempt operations
+    // Use an invalid host to verify the connection object works but fails as expected
+    let result = connection.execute("echo test").await;
+
+    // Should fail because no host is configured, but the connection object should work
+    match result {
+        Ok((exit_code, _)) => assert!(exit_code != 0), // Should fail due to missing host
+        Err(_) => {} // Error is expected when no host is configured
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_host_functionality() {
+    // Test that setting a host actually affects connection behavior
+    let connection = SshConnectionBuilder::new()
+        .host("nonexistent-host-12345.invalid")
+        .user("testuser")
+        .timeout(Duration::from_millis(100))
+        .build();
+
+    // This should fail because the host doesn't exist
+    let result = connection.execute("echo test").await;
+    match result {
+        Ok((exit_code, _)) => assert!(exit_code != 0), // Should fail
+        Err(_) => {}                                   // Error is expected for invalid hosts
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_port_functionality() {
+    // Test that setting a custom port affects connection behavior
+    let connection = SshConnectionBuilder::new()
+        .host("127.0.0.1")
+        .port(12345) // Non-standard SSH port that should be closed
+        .user("testuser")
+        .timeout(Duration::from_millis(100))
+        .build();
+
+    // This should fail because port 12345 is not running SSH
+    let result = connection.ping().await;
+    match result {
+        Ok(success) => assert!(!success), // Should fail to connect
+        Err(_) => {}                      // Error is expected for closed ports
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_user_functionality() {
+    // Test that setting a user affects connection behavior
+    let connection = SshConnectionBuilder::new()
+        .host("127.0.0.1")
+        .user("nonexistent-user-12345")
+        .timeout(Duration::from_millis(100))
+        .build();
+
+    // This should fail because the user doesn't exist
+    let result = connection.execute("whoami").await;
+    match result {
+        Ok((exit_code, _)) => assert!(exit_code != 0), // Should fail
+        Err(_) => {}                                   // Error is expected for invalid users
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_identity_file() {
+    // Test that setting an identity file affects connection behavior
+    let path = PathBuf::from("/nonexistent/path/to/key");
+    let connection = SshConnectionBuilder::new()
+        .host("127.0.0.1")
+        .user("testuser")
+        .identity_file(path)
+        .timeout(Duration::from_millis(100))
+        .build();
+
+    // Test that connection with identity file attempts operations but fails as expected
+    let result = connection.ping().await;
+
+    // Should fail due to invalid key file or authentication, but connection should work
+    match result {
+        Ok(success) => assert!(!success), // Should fail due to invalid key or auth
+        Err(_) => {}                      // Error is expected for invalid key file
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_timeout_functionality() {
+    // Test that timeout setting actually affects connection behavior
+    let short_timeout = Duration::from_secs(1); // More reasonable timeout
+    let connection = SshConnectionBuilder::new()
+        .host("10.255.255.1") // Non-routable IP to trigger timeout
+        .timeout(short_timeout)
+        .build();
+
+    let start = std::time::Instant::now();
+    let result = connection.ping().await;
+    let elapsed = start.elapsed();
+
+    // Should timeout reasonably quickly (within 10 seconds)
+    assert!(elapsed < Duration::from_secs(10));
+    match result {
+        Ok(success) => assert!(!success), // Should timeout/fail
+        Err(_) => {}                      // Error is expected for timeouts
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_chaining() {
+    // Test that method chaining works and produces a functional connection
+    let connection = SshConnectionBuilder::new()
+        .host("invalid-host-12345.test")
+        .port(2222)
+        .user("testuser")
+        .timeout(Duration::from_millis(100))
+        .build();
+
+    // Test that the chained configuration actually works
+    let result = connection.ping().await;
+    match result {
+        Ok(success) => assert!(!success), // Should fail to connect to invalid host
+        Err(_) => {}                      // Error is expected for invalid hosts
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_execute_invalid_host() {
+    let connection = SshConnectionBuilder::new()
+        .host("this-host-definitely-does-not-exist-12345")
+        .user("testuser")
+        .timeout(Duration::from_secs(1))
+        .build();
+
+    let result = connection.execute("echo 'test'").await;
+
+    // Should fail because host doesn't exist
+    // Note: This test depends on SSH client being available
+    match result {
+        Ok((exit_code, _output)) => {
+            // SSH might return various exit codes for connection failures
+            assert!(exit_code != 0); // Should not succeed
+        }
+        Err(_) => {
+            // Error is also acceptable (SSH client might not be available)
+            // This is expected behavior for invalid hosts
+        }
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_execute_localhost_no_auth() {
+    let connection = SshConnectionBuilder::new()
+        .host("localhost")
+        .user("nonexistentuser12345")
+        .timeout(Duration::from_secs(1))
+        .build();
+
+    let result = connection.execute("echo 'test'").await;
+
+    // Should fail due to authentication/user issues
+    match result {
+        Ok((exit_code, _output)) => {
+            // SSH should fail with non-zero exit code
+            assert!(exit_code != 0);
+        }
+        Err(_) => {
+            // Error is also acceptable (SSH client might not be available)
+            // This is expected behavior for authentication failures
+        }
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_ping_invalid_host() {
+    let connection = SshConnectionBuilder::new()
+        .host("this-host-definitely-does-not-exist-12345")
+        .user("testuser")
+        .timeout(Duration::from_secs(1))
+        .build();
+
+    let result = connection.ping().await;
+
+    match result {
+        Ok(success) => {
+            assert!(!success); // Should not succeed
+        }
+        Err(_) => {
+            // Error is also acceptable for invalid hosts
+            // This is expected behavior
+        }
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_ping_localhost_no_auth() {
+    let connection = SshConnectionBuilder::new()
+        .host("localhost")
+        .user("nonexistentuser12345")
+        .timeout(Duration::from_secs(1))
+        .build();
+
+    let result = connection.ping().await;
+
+    match result {
+        Ok(success) => {
+            // Should fail due to authentication issues
+            assert!(!success);
+        }
+        Err(_) => {
+            // Error is also acceptable for authentication failures
+            // This is expected behavior
+        }
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_default_values() {
+    // Test that builder creates connection with reasonable defaults
+    let connection = SshConnectionBuilder::new().build();
+
+    // Test that default connection can attempt operations but fails gracefully
+    let result = connection.ping().await;
+
+    // Should fail because no host is configured, but should handle it gracefully
+    match result {
+        Ok(success) => assert!(!success), // Should fail due to missing host
+        Err(_) => {}                      // Error is expected when no host is configured
+    }
+}
+
+#[tokio::test]
+async fn test_ssh_connection_builder_full_config() {
+    // Test builder with all options set
+    let connection = SshConnectionBuilder::new()
+        .host("nonexistent-host-12345.invalid")
+        .port(2222)
+        .user("testuser")
+        .identity_file(PathBuf::from("/nonexistent/path/to/key"))
+        .timeout(Duration::from_millis(100))
+        .build();
+
+    // Test that fully configured connection attempts operations but fails as expected
+    let result = connection.ping().await;
+
+    // Should fail because host doesn't exist, but all configuration should be applied
+    match result {
+        Ok(success) => assert!(!success), // Should fail due to invalid host
+        Err(_) => {}                      // Error is expected for invalid host
+    }
+}
+
+// Integration test that requires actual SSH setup
+// This test is disabled by default as it requires SSH server and keys
+#[tokio::test]
+#[ignore]
+async fn test_ssh_execute_real_connection() {
+    // This test would require:
+    // 1. SSH server running on localhost
+    // 2. Valid SSH keys set up
+    // 3. User account configured
+
+    let connection = SshConnectionBuilder::new()
+        .host("localhost")
+        .user("testuser") // Replace with actual user
+        .build();
+
+    let result = connection.execute("echo 'Hello from SSH'").await;
+
+    match result {
+        Ok((exit_code, output)) => {
+            assert_eq!(exit_code, 0);
+            assert!(output.contains("Hello from SSH"));
+        }
+        Err(e) => {
+            panic!("SSH execution failed: {}", e);
+        }
+    }
+}