fix(sling): auto-attach work molecule and handle dead polecats

Combines three related sling improvements:

1. Auto-attach mol-polecat-work (Issue #288)
   - Automatically attach work molecule when slinging to polecats
   - Ensures polecats have standard guidance molecule attached

2. Fix polecat hook with molecule (Issue #197)
   - Use beads.ResolveHookDir() for correct directory resolution
   - Prevents bd cook from failing in polecat worktree

3. Spawn fresh polecat when target has no session
   - When slinging to a dead polecat, spawn fresh one instead of failing
   - Fixes stale convoys not progressing due to done polecats

internal/cmd/sling_helpers.go

@@ -9,7 +9,9 @@ import (
 	"time"
 
 	"github.com/steveyegge/gastown/internal/beads"
+	"github.com/steveyegge/gastown/internal/config"
 	"github.com/steveyegge/gastown/internal/constants"
+	"github.com/steveyegge/gastown/internal/style"
 	"github.com/steveyegge/gastown/internal/tmux"
 	"github.com/steveyegge/gastown/internal/workspace"
 )
@@ -373,3 +375,67 @@ func wakeRigAgents(rigName string) {
 	_ = t.NudgeSession(witnessSession, "Polecat dispatched - check for work")
 	_ = t.NudgeSession(refinerySession, "Polecat dispatched - check for merge requests")
 }
+
+// isPolecatTarget checks if the target string refers to a polecat.
+// Returns true if the target format is "rig/polecats/name".
+// This is used to determine if we should respawn a dead polecat
+// instead of failing when slinging work.
+func isPolecatTarget(target string) bool {
+	parts := strings.Split(target, "/")
+	return len(parts) >= 3 && parts[1] == "polecats"
+}
+
+// attachPolecatWorkMolecule attaches the mol-polecat-work molecule to a polecat's agent bead.
+// This ensures all polecats have the standard work molecule attached for guidance.
+// The molecule is attached by storing it in the agent bead's description using attachment fields.
+//
+// Per issue #288: gt sling should auto-attach mol-polecat-work when slinging to polecats.
+func attachPolecatWorkMolecule(targetAgent, hookWorkDir, townRoot string) error {
+	// Parse the polecat name from targetAgent (format: "rig/polecats/name")
+	parts := strings.Split(targetAgent, "/")
+	if len(parts) != 3 || parts[1] != "polecats" {
+		return fmt.Errorf("invalid polecat agent format: %s", targetAgent)
+	}
+	rigName := parts[0]
+	polecatName := parts[2]
+
+	// Get the polecat's agent bead ID
+	// Format: "<prefix>-<rig>-polecat-<name>" (e.g., "gt-gastown-polecat-Toast")
+	prefix := config.GetRigPrefix(townRoot, rigName)
+	agentBeadID := beads.PolecatBeadIDWithPrefix(prefix, rigName, polecatName)
+
+	// Resolve the rig directory for running bd commands.
+	// Use ResolveHookDir to ensure we run bd from the correct rig directory
+	// (not from the polecat's worktree, which doesn't have a .beads directory).
+	// This fixes issue #197: polecat fails to hook when slinging with molecule.
+	rigDir := beads.ResolveHookDir(townRoot, prefix+"-"+polecatName, hookWorkDir)
+
+	b := beads.New(rigDir)
+
+	// Check if molecule is already attached (avoid duplicate attach)
+	attachment, err := b.GetAttachment(agentBeadID)
+	if err == nil && attachment != nil && attachment.AttachedMolecule != "" {
+		// Already has a molecule attached - skip
+		return nil
+	}
+
+	// Cook the mol-polecat-work formula to ensure the proto exists
+	// This is safe to run multiple times - cooking is idempotent
+	cookCmd := exec.Command("bd", "--no-daemon", "cook", "mol-polecat-work")
+	cookCmd.Dir = rigDir
+	cookCmd.Stderr = os.Stderr
+	if err := cookCmd.Run(); err != nil {
+		return fmt.Errorf("cooking mol-polecat-work formula: %w", err)
+	}
+
+	// Attach the molecule to the polecat's agent bead
+	// The molecule ID is the formula name "mol-polecat-work"
+	moleculeID := "mol-polecat-work"
+	_, err = b.AttachMolecule(agentBeadID, moleculeID)
+	if err != nil {
+		return fmt.Errorf("attaching molecule %s to %s: %w", moleculeID, agentBeadID, err)
+	}
+
+	fmt.Printf("%s Attached %s to %s\n", style.Bold.Render("✓"), moleculeID, agentBeadID)
+	return nil
+}