fix(namepool): read polecat_names from rig config.json as fallback + warn on missing theme

NewManager only read namepool config from settings/config.json. If that
file was missing but the rig's config.json had polecat_names configured,
the names were ignored and ThemeForRig hash was used instead.

Now checks rig config.json for polecat_names when settings/config.json
has no namepool config. Also logs a warning when a configured theme name
can't be resolved (instead of silently falling back to default).

Fixes: #3594

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: emmett

internal/polecat/manager.go

@@ -176,8 +176,13 @@ func NewManager(r *rig.Rig, g *git.Git, t *tmux.Tmux) *Manager {
 			settings.Namepool.MaxBeforeNumbering,
 		)
 	} else {
-		// Use defaults
-		pool = NewNamePool(r.Path, r.Name)
+		// Fallback: check rig-level config.json for polecat_names
+		// (pool-init and gt rig config write namepool config here).
+		if rigCfg, rcErr := rig.LoadRigConfig(r.Path); rcErr == nil && len(rigCfg.PolecatNames) > 0 {
+			pool = NewNamePoolWithConfig(r.Path, r.Name, "", rigCfg.PolecatNames, 0)
+		} else {
+			pool = NewNamePool(r.Path, r.Name)
+		}
 	}
 
 	// Set town root for custom theme resolution in getNames()

internal/polecat/manager_test.go

@@ -275,6 +275,32 @@ func TestAgentBeadID_Deterministic(t *testing.T) {
 	}
 }
 
+func TestNewManager_NamepoolFromRigConfig(t *testing.T) {
+	townRoot := t.TempDir()
+	rigPath := filepath.Join(townRoot, "myrig")
+	if err := os.MkdirAll(rigPath, 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	// Write rig config.json with polecat_names (no settings/config.json)
+	rigConfig := `{"polecat_names": ["alpha", "beta", "gamma"]}`
+	if err := os.WriteFile(filepath.Join(rigPath, "config.json"), []byte(rigConfig), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	r := &rig.Rig{Name: "myrig", Path: rigPath}
+	m := NewManager(r, git.NewGit(rigPath), nil)
+	pool := m.GetNamePool()
+
+	name, err := pool.Allocate()
+	if err != nil {
+		t.Fatalf("Allocate error: %v", err)
+	}
+	if name != "alpha" {
+		t.Errorf("expected first name from rig config (alpha), got %q", name)
+	}
+}
+
 // Note: State persistence tests removed - state is now derived from beads assignee field.
 // Integration tests should verify beads-based state management.
 

internal/polecat/namepool.go

@@ -174,6 +174,7 @@ func (p *NamePool) getNames() []string {
 		if resolved, err := ResolveThemeNames(p.townRoot, p.Theme); err == nil {
 			names = resolved
 		} else {
+			fmt.Fprintf(os.Stderr, "Warning: namepool theme %q not found (not built-in, no custom theme file); using default\n", p.Theme)
 			names = BuiltinThemes[DefaultTheme]
 		}
 	} else {

internal/polecat/namepool_test.go

@@ -1228,3 +1228,26 @@ func TestGetNames_FallbackOnDeletedThemeFile(t *testing.T) {
 		t.Errorf("expected fallback to default theme (furiosa), got %s", name)
 	}
 }
+
+func TestGetNames_UnresolvableTheme_FallsBackToDefault(t *testing.T) {
+	tmpDir := t.TempDir()
+
+	pool := NewNamePoolWithConfig(tmpDir, "testrig", "nonexistent-theme", nil, 10)
+	pool.SetTownRoot(tmpDir)
+
+	name, err := pool.Allocate()
+	if err != nil {
+		t.Fatalf("Allocate error: %v", err)
+	}
+	defaultNames := BuiltinThemes[DefaultTheme]
+	found := false
+	for _, dn := range defaultNames {
+		if dn == name {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Errorf("expected name from default theme, got %q", name)
+	}
+}