feat: add CLI core commands (status, prime, init)

- status: Show town status with rig/polecat/witness counts (--json supported)
- prime: Output role context based on current directory
- init: Initialize a git repo as a Gas Town rig

Closes gt-u1j.10

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

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

internal/cmd/init.go

@@ -0,0 +1,141 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+	"github.com/steveyegge/gastown/internal/git"
+	"github.com/steveyegge/gastown/internal/rig"
+	"github.com/steveyegge/gastown/internal/style"
+)
+
+var initForce bool
+
+var initCmd = &cobra.Command{
+	Use:   "init",
+	Short: "Initialize current directory as a Gas Town rig",
+	Long: `Initialize the current directory for use as a Gas Town rig.
+
+This creates the standard agent directories (polecats/, witness/, refinery/,
+mayor/) and updates .git/info/exclude to ignore them.
+
+The current directory must be a git repository. Use --force to reinitialize
+an existing rig structure.`,
+	RunE: runInit,
+}
+
+func init() {
+	initCmd.Flags().BoolVarP(&initForce, "force", "f", false, "Reinitialize existing structure")
+	rootCmd.AddCommand(initCmd)
+}
+
+func runInit(cmd *cobra.Command, args []string) error {
+	cwd, err := os.Getwd()
+	if err != nil {
+		return fmt.Errorf("getting current directory: %w", err)
+	}
+
+	// Check if it's a git repository
+	g := git.NewGit(cwd)
+	if _, err := g.CurrentBranch(); err != nil {
+		return fmt.Errorf("not a git repository (run 'git init' first)")
+	}
+
+	// Check if already initialized
+	polecatsDir := filepath.Join(cwd, "polecats")
+	if _, err := os.Stat(polecatsDir); err == nil && !initForce {
+		return fmt.Errorf("rig already initialized (use --force to reinitialize)")
+	}
+
+	fmt.Printf("%s Initializing Gas Town rig in %s\n\n",
+		style.Bold.Render("⚙️"), style.Dim.Render(cwd))
+
+	// Create agent directories
+	created := 0
+	for _, dir := range rig.AgentDirs {
+		dirPath := filepath.Join(cwd, dir)
+		if err := os.MkdirAll(dirPath, 0755); err != nil {
+			return fmt.Errorf("creating %s: %w", dir, err)
+		}
+
+		// Create .gitkeep to ensure directory is tracked if needed
+		gitkeep := filepath.Join(dirPath, ".gitkeep")
+		if _, err := os.Stat(gitkeep); os.IsNotExist(err) {
+			os.WriteFile(gitkeep, []byte(""), 0644)
+		}
+
+		fmt.Printf("   ✓ Created %s/\n", dir)
+		created++
+	}
+
+	// Update .git/info/exclude
+	if err := updateGitExclude(cwd); err != nil {
+		fmt.Printf("   %s Could not update .git/info/exclude: %v\n",
+			style.Dim.Render("⚠"), err)
+	} else {
+		fmt.Printf("   ✓ Updated .git/info/exclude\n")
+	}
+
+	fmt.Printf("\n%s Rig initialized with %d directories.\n",
+		style.Bold.Render("✓"), created)
+	fmt.Println()
+	fmt.Println("Next steps:")
+	fmt.Printf("  1. Add this rig to a town: %s\n",
+		style.Dim.Render("gt rig add <name> <git-url>"))
+	fmt.Printf("  2. Create a polecat: %s\n",
+		style.Dim.Render("gt polecat add <name>"))
+
+	return nil
+}
+
+func updateGitExclude(repoPath string) error {
+	excludePath := filepath.Join(repoPath, ".git", "info", "exclude")
+
+	// Ensure directory exists
+	excludeDir := filepath.Dir(excludePath)
+	if err := os.MkdirAll(excludeDir, 0755); err != nil {
+		return fmt.Errorf("creating .git/info: %w", err)
+	}
+
+	// Read existing content
+	content, err := os.ReadFile(excludePath)
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	// Check if already has Gas Town section
+	contentStr := string(content)
+	if len(content) > 0 && contains(contentStr, "Gas Town") {
+		return nil // Already configured
+	}
+
+	// Append agent dirs
+	additions := "\n# Gas Town agent directories\n"
+	for _, dir := range rig.AgentDirs {
+		// Get first component (e.g., "polecats" from "polecats")
+		// or "refinery" from "refinery/rig"
+		base := filepath.Dir(dir)
+		if base == "." {
+			base = dir
+		}
+		additions += base + "/\n"
+	}
+
+	// Write back
+	return os.WriteFile(excludePath, append(content, []byte(additions)...), 0644)
+}
+
+func contains(s, substr string) bool {
+	return len(s) >= len(substr) && (s == substr || len(s) > 0 && containsHelper(s, substr))
+}
+
+func containsHelper(s, substr string) bool {
+	for i := 0; i <= len(s)-len(substr); i++ {
+		if s[i:i+len(substr)] == substr {
+			return true
+		}
+	}
+	return false
+}