Merge polecat/Valkyrie: keepalive signal from gt commands

Adds keepalive.Touch() to signal agent activity during commands.
Also ignores state.json in .gitignore.

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

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

internal/cmd/root.go

@@ -3,8 +3,10 @@ package cmd
 
 import (
 	"os"
+	"strings"
 
 	"github.com/spf13/cobra"
+	"github.com/steveyegge/gastown/internal/keepalive"
 )
 
 var rootCmd = &cobra.Command{
@@ -14,6 +16,12 @@ var rootCmd = &cobra.Command{
 
 It coordinates agent spawning, work distribution, and communication
 across distributed teams of AI agents working on shared codebases.`,
+	PersistentPreRun: func(cmd *cobra.Command, args []string) {
+		// Signal agent activity by touching keepalive file
+		// Build command path: gt status, gt mail send, etc.
+		cmdPath := buildCommandPath(cmd)
+		keepalive.TouchWithArgs(cmdPath, args)
+	},
 }
 
 // Execute runs the root command
@@ -27,3 +35,13 @@ func init() {
 	// Global flags can be added here
 	// rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file")
 }
+
+// buildCommandPath walks the command hierarchy to build the full command path.
+// For example: "gt mail send", "gt status", etc.
+func buildCommandPath(cmd *cobra.Command) string {
+	var parts []string
+	for c := cmd; c != nil; c = c.Parent() {
+		parts = append([]string{c.Name()}, parts...)
+	}
+	return strings.Join(parts, " ")
+}