feat: add Cobra CLI scaffolding with Lipgloss styles

- cmd/gt/main.go: Entry point using Cobra
- internal/cmd/root.go: Root command with description
- internal/cmd/version.go: Version command with build info
- internal/style/style.go: Lipgloss styles for terminal output

Closes gt-u1j.1

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/cmd/version.go

@@ -0,0 +1,30 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"github.com/steveyegge/gastown/internal/style"
+)
+
+// Version information - set at build time via ldflags
+var (
+	Version   = "0.1.0"
+	BuildTime = "unknown"
+	GitCommit = "unknown"
+)
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Print version information",
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Println(style.Bold.Render("gt") + " - Gas Town CLI")
+		fmt.Printf("Version:  %s\n", Version)
+		fmt.Printf("Commit:   %s\n", style.Dim.Render(GitCommit))
+		fmt.Printf("Built:    %s\n", style.Dim.Render(BuildTime))
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+}