feat: implement connect host command with native SSH

- Add connect command with native SSH (default) and direct Go SSH (--direct) modes
- Support host lookup by name or ID
- Build SSH arguments for system SSH client
- Include timeout configuration flag
- Add comprehensive tests for command and SSH arg building
- Update project state documentation

cmd/hostkeeper/connect.go

@@ -0,0 +1,161 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/exec"
+	"time"
+
+	"github.com/spf13/cobra"
+
+	"git.tukangketik.id/swanadiva/hostkeeper/internal/errors"
+	"git.tukangketik.id/swanadiva/hostkeeper/internal/models"
+	"git.tukangketik.id/swanadiva/hostkeeper/pkg/config"
+	"git.tukangketik.id/swanadiva/hostkeeper/pkg/ssh"
+	"git.tukangketik.id/swanadiva/hostkeeper/pkg/storage"
+)
+
+var (
+	connectTimeout int
+	connectDirect  bool
+)
+
+// connectCmd represents the connect command
+var connectCmd = &cobra.Command{
+	Use:   "connect <host-name-or-id>",
+	Short: "Connect to a saved SSH host",
+	Long: `Connect to a saved SSH host using native SSH client with stored credentials.
+
+Examples:
+  # Connect to a host by name
+  hostkeeper connect myserver
+
+  # Connect with a specific timeout
+  hostkeeper connect myserver --timeout 60
+
+  # Use Go SSH client (direct mode) instead of system SSH
+  hostkeeper connect myserver --direct`,
+	Args: cobra.ExactArgs(1),
+	RunE: runConnect,
+}
+
+func init() {
+	connectCmd.Flags().IntVar(&connectTimeout, "timeout", 30, "Connection timeout in seconds")
+	connectCmd.Flags().BoolVar(&connectDirect, "direct", false, "Use direct SSH instead of native client")
+
+	rootCmd.AddCommand(connectCmd)
+}
+
+func runConnect(cmd *cobra.Command, args []string) error {
+	hostIdentifier := args[0]
+
+	cfg := appCfg
+	if cfg == nil {
+		var err error
+		cfg, err = config.New()
+		if err != nil {
+			return fmt.Errorf("failed to initialize config: %w", err)
+		}
+	}
+
+	// Initialize storage
+	store, err := storage.NewJSONStorage(cfg.GetDataDir())
+	if err != nil {
+		return fmt.Errorf("failed to initialize storage: %w", err)
+	}
+
+	ctx := context.Background()
+
+	// Find host by name or ID
+	host, err := findHost(ctx, store, hostIdentifier)
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("Connecting to %s (%s@%s:%d)...\n", host.Name, host.Username, host.Hostname, host.Port)
+
+	// Choose connection method
+	if connectDirect {
+		return connectDirectSSH(host)
+	}
+
+	return connectWithNativeSSH(host)
+}
+
+// findHost finds a host by ID first, then by name
+func findHost(ctx context.Context, store storage.Storage, identifier string) (*models.Host, error) {
+	// Try to find by ID first
+	host, err := store.GetHost(ctx, identifier)
+	if err == nil {
+		return host, nil
+	}
+
+	// Try to find by name
+	hosts, err := store.ListHosts(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to list hosts: %w", err)
+	}
+
+	for _, h := range hosts {
+		if h.Name == identifier {
+			return h, nil
+		}
+	}
+
+	// Host not found, provide helpful error
+	return nil, fmt.Errorf("host '%s' not found. Use 'hostkeeper list' to see available hosts", identifier)
+}
+
+// connectWithNativeSSH uses the system SSH client
+func connectWithNativeSSH(host *models.Host) error {
+	sshArgs := buildSSHArgs(host)
+
+	cmd := exec.Command("ssh", sshArgs...)
+
+	// Set up standard I/O for interactive session
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+
+	// Execute SSH command
+	if err := cmd.Run(); err != nil {
+		return errors.HandleSSHError(err)
+	}
+
+	return nil
+}
+
+// connectDirectSSH uses Go SSH client
+func connectDirectSSH(host *models.Host) error {
+	timeout := time.Duration(connectTimeout) * time.Second
+	client := ssh.NewClient(host, timeout)
+
+	ctx := context.Background()
+	if err := client.Connect(ctx); err != nil {
+		return err
+	}
+	defer client.Close()
+
+	fmt.Printf("Connected to %s\n", host.Name)
+	fmt.Println("Interactive shell not yet implemented in direct mode")
+	fmt.Println("Use --direct=false (default) for native SSH experience")
+
+	return nil
+}
+
+// buildSSHArgs builds SSH command arguments for the system SSH client
+func buildSSHArgs(host *models.Host) []string {
+	var args []string
+
+	// Add port if not default
+	if host.Port != 22 && host.Port != 0 {
+		args = append(args, "-p", fmt.Sprintf("%d", host.Port))
+	}
+
+	// Add connection string
+	connectionString := fmt.Sprintf("%s@%s", host.Username, host.Hostname)
+	args = append(args, connectionString)
+
+	return args
+}