feat: add setup & remove cmd for better UX (#43)

* feat: add setup & remove cmd for better UX

* refactor(alias): improve separation of concerns and fix shell sourcing

* chore: remove extra/unused folder

* refactor: introduce separate files for shells

* fix: use temp files for safe shell config modification

cmd/setup/setup.go

@@ -0,0 +1,55 @@
+package setup
+
+import (
+	"github.com/safedep/pmg/internal/alias"
+	"github.com/spf13/cobra"
+)
+
+func NewSetupCommand() *cobra.Command {
+	setupCmd := &cobra.Command{
+		Use:   "setup",
+		Short: "Manage PMG shell aliases and integration",
+		Long:  "Setup and manage PMG shell aliases that allow you to use 'npm', 'pnpm', 'pip' commands through PMG's security wrapper.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return cmd.Help()
+		},
+	}
+
+	setupCmd.AddCommand(NewInstallCommand())
+	setupCmd.AddCommand(NewRemoveCommand())
+
+	return setupCmd
+}
+
+func NewInstallCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:   "install",
+		Short: "Install PMG aliases for package managers (npm, pnpm, pip)",
+		Long:  "Creates ~/.pmg.rc with package manager aliases and sources it in your shell config files (.bashrc, .zshrc, config.fish)",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			config := alias.DefaultConfig()
+			rcFileManager, err := alias.NewDefaultRcFileManager(config.RcFileName)
+			if err != nil {
+				return err
+			}
+			aliasManager := alias.New(*config, rcFileManager)
+			return aliasManager.Install()
+		},
+	}
+}
+
+func NewRemoveCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:   "remove",
+		Short: "Removes pmg aliases from the user's shell config file.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			config := alias.DefaultConfig()
+			rcFileManager, err := alias.NewDefaultRcFileManager(config.RcFileName)
+			if err != nil {
+				return err
+			}
+			aliasManager := alias.New(*config, rcFileManager)
+			return aliasManager.Remove()
+		},
+	}
+}