Add Claude settings templates for autonomous roles (gt-6957)

- Create internal/claude package with embedded settings templates
- settings-autonomous.json: gt prime && gt mail check --inject (SessionStart)
- settings-interactive.json: gt prime only (SessionStart)

- Update witness.go: EnsureSettings before session, remove broken gt prime injection
- Update refinery/manager.go: EnsureSettings before session, remove broken NudgeSession
- Update session/manager.go: EnsureSettings for polecats, remove broken issue injection

All autonomous roles (polecat, witness, refinery) now get proper SessionStart hooks
automatically when their sessions are created. No more timing-based gt prime injection.

internal/claude/config/settings-autonomous.json

@@ -0,0 +1,40 @@
+{
+  "enabledPlugins": {
+    "beads@beads-marketplace": false
+  },
+  "hooks": {
+    "SessionStart": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "gt prime && gt mail check --inject"
+          }
+        ]
+      }
+    ],
+    "PreCompact": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "gt prime"
+          }
+        ]
+      }
+    ],
+    "UserPromptSubmit": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "gt mail check --inject"
+          }
+        ]
+      }
+    ]
+  }
+}

internal/claude/config/settings-interactive.json

@@ -0,0 +1,40 @@
+{
+  "enabledPlugins": {
+    "beads@beads-marketplace": false
+  },
+  "hooks": {
+    "SessionStart": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "gt prime"
+          }
+        ]
+      }
+    ],
+    "PreCompact": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "gt prime"
+          }
+        ]
+      }
+    ],
+    "UserPromptSubmit": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "gt mail check --inject"
+          }
+        ]
+      }
+    ]
+  }
+}

internal/claude/settings.go

@@ -0,0 +1,80 @@
+// Package claude provides Claude Code configuration management.
+package claude
+
+import (
+	"embed"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+//go:embed config/*.json
+var configFS embed.FS
+
+// RoleType indicates whether a role is autonomous or interactive.
+type RoleType string
+
+const (
+	// Autonomous roles (polecat, witness, refinery) need mail in SessionStart
+	// because they may be triggered externally without user input.
+	Autonomous RoleType = "autonomous"
+
+	// Interactive roles (mayor, crew) wait for user input, so UserPromptSubmit
+	// handles mail injection.
+	Interactive RoleType = "interactive"
+)
+
+// RoleTypeFor returns the RoleType for a given role name.
+func RoleTypeFor(role string) RoleType {
+	switch role {
+	case "polecat", "witness", "refinery":
+		return Autonomous
+	default:
+		return Interactive
+	}
+}
+
+// EnsureSettings ensures .claude/settings.json exists in the given directory.
+// If the file doesn't exist, it copies the appropriate template based on role type.
+// If the file already exists, it's left unchanged.
+func EnsureSettings(workDir string, roleType RoleType) error {
+	claudeDir := filepath.Join(workDir, ".claude")
+	settingsPath := filepath.Join(claudeDir, "settings.json")
+
+	// If settings already exist, don't overwrite
+	if _, err := os.Stat(settingsPath); err == nil {
+		return nil
+	}
+
+	// Create .claude directory if needed
+	if err := os.MkdirAll(claudeDir, 0755); err != nil {
+		return fmt.Errorf("creating .claude directory: %w", err)
+	}
+
+	// Select template based on role type
+	var templateName string
+	switch roleType {
+	case Autonomous:
+		templateName = "config/settings-autonomous.json"
+	default:
+		templateName = "config/settings-interactive.json"
+	}
+
+	// Read template
+	content, err := configFS.ReadFile(templateName)
+	if err != nil {
+		return fmt.Errorf("reading template %s: %w", templateName, err)
+	}
+
+	// Write settings file
+	if err := os.WriteFile(settingsPath, content, 0644); err != nil {
+		return fmt.Errorf("writing settings: %w", err)
+	}
+
+	return nil
+}
+
+// EnsureSettingsForRole is a convenience function that combines RoleTypeFor and EnsureSettings.
+func EnsureSettingsForRole(workDir, role string) error {
+	return EnsureSettings(workDir, RoleTypeFor(role))
+}