fix: Add grace period to prevent Deacon restart loop (#590)

* fix(daemon): prevent runaway refinery session spawning

Fixes #566

The daemon spawned 812 refinery sessions over 4 days because:

1. Zombie detection was too strict - used IsAgentRunning(session, "node")
   but Claude reports pane command as version number (e.g., "2.1.7"),
   causing healthy sessions to be killed and recreated every heartbeat.

2. daemon.json patrol config was completely ignored - the daemon never
   loaded or checked the enabled flags.

Changes:
- refinery/manager.go: Use IsClaudeRunning() instead of IsAgentRunning()
  for robust Claude detection (handles "node", "claude", version patterns)
- daemon/types.go: Add PatrolConfig types and LoadPatrolConfig() to read
  mayor/daemon.json
- daemon/daemon.go: Load patrol config at startup, check enabled flags
  before calling ensureRefineriesRunning/ensureWitnessesRunning, add
  diagnostic logging for "already running" cases

Tested: Verified over multiple heartbeats that refinery shows "already
running, skipping spawn" instead of spawning new sessions.

* fix: Add grace period to prevent Deacon restart loop

The daemon had a race condition where:
1. ensureDeaconRunning() starts a new Deacon session
2. checkDeaconHeartbeat() runs in same heartbeat cycle
3. Heartbeat file is stale (from before crash)
4. Session is immediately killed
5. Infinite restart loop every 3 minutes

Fix:
- Track when Deacon was last started (deaconLastStarted field)
- Skip heartbeat check during 5-minute grace period
- Add config support for Deacon (consistency with refinery/witness)

After grace period, normal heartbeat checking resumes. Genuinely
stuck sessions (no heartbeat update after 5+ min) are still detected.

Fixes #589

---------

Co-authored-by: mayor <your-github-email@example.com>

internal/daemon/patrol_config_test.go

@@ -0,0 +1,53 @@
+package daemon
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestLoadPatrolConfig(t *testing.T) {
+	// Create a temp dir with test config
+	tmpDir := t.TempDir()
+	mayorDir := filepath.Join(tmpDir, "mayor")
+	if err := os.MkdirAll(mayorDir, 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	// Write test config
+	configJSON := `{
+		"type": "daemon-patrol-config",
+		"version": 1,
+		"patrols": {
+			"refinery": {"enabled": false},
+			"witness": {"enabled": true}
+		}
+	}`
+	if err := os.WriteFile(filepath.Join(mayorDir, "daemon.json"), []byte(configJSON), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	// Load config
+	config := LoadPatrolConfig(tmpDir)
+	if config == nil {
+		t.Fatal("expected config to be loaded")
+	}
+
+	// Test enabled flags
+	if IsPatrolEnabled(config, "refinery") {
+		t.Error("expected refinery to be disabled")
+	}
+	if !IsPatrolEnabled(config, "witness") {
+		t.Error("expected witness to be enabled")
+	}
+	if !IsPatrolEnabled(config, "deacon") {
+		t.Error("expected deacon to be enabled (default)")
+	}
+}
+
+func TestIsPatrolEnabled_NilConfig(t *testing.T) {
+	// Should default to enabled when config is nil
+	if !IsPatrolEnabled(nil, "refinery") {
+		t.Error("expected default to be enabled")
+	}
+}