v0.24.0 — Pre-testing observability: debug logging, diagnostic dump, startup self-test

- Add [DEBUG] logging across all modules (backup, storage, sync, selfupdate,
  monitor, notify, report, assets, setup) gated behind logging.level: "debug"
- Add /api/debug/dump endpoint returning full controller state JSON (debug only)
- Add startup self-test validating 9 subsystems (Docker, dirs, storage, hub,
  restic repos, metrics DB) with pass/warn/fail summary
- New packages: internal/selftest, internal/util
- Constructor/signature changes: debug bool params, logger params on
  RunHealthCheck and BuildReport, smart watchdog probe logging

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

controller/internal/notify/notifier.go

@@ -23,6 +23,7 @@ type Notifier struct {
 	httpClient *http.Client
 	logger     *log.Logger
 	enabled    bool
+	debug      bool
 	settings   *settings.Settings
 
 	mu               sync.Mutex
@@ -30,7 +31,7 @@ type Notifier struct {
 }
 
 // New creates a new Notifier. Returns a no-op notifier if hub is not enabled.
-func New(hubURL, apiKey, customerID string, sett *settings.Settings, logger *log.Logger) *Notifier {
+func New(hubURL, apiKey, customerID string, sett *settings.Settings, logger *log.Logger, debug bool) *Notifier {
 	enabled := hubURL != "" && apiKey != ""
 	if enabled {
 		logger.Printf("[INFO] Notifier enabled (hub: %s)", hubURL)
@@ -45,6 +46,7 @@ func New(hubURL, apiKey, customerID string, sett *settings.Settings, logger *log
 		httpClient: &http.Client{Timeout: 10 * time.Second},
 		logger:     logger,
 		enabled:    enabled,
+		debug:      debug,
 		settings:   sett,
 	}
 }
@@ -162,6 +164,9 @@ func (n *Notifier) PushEvent(eventType, severity, message string, details interf
 
 	go func() {
 		url := n.hubURL + "/api/v1/event"
+		if n.debug {
+			n.logger.Printf("[DEBUG] PushEvent: type=%s severity=%s url=%s", eventType, severity, url)
+		}
 		var lastErr error
 		for attempt := 0; attempt < 3; attempt++ {
 			if attempt > 0 {
@@ -185,6 +190,9 @@ func (n *Notifier) PushEvent(eventType, severity, message string, details interf
 			resp.Body.Close()
 
 			if resp.StatusCode >= 200 && resp.StatusCode < 300 {
+				if n.debug {
+					n.logger.Printf("[DEBUG] PushEvent: %s pushed OK (HTTP %d)", eventType, resp.StatusCode)
+				}
 				n.logger.Printf("[INFO] Event pushed: %s (%s) — %s", eventType, severity, message)
 				return
 			}
@@ -284,9 +292,10 @@ func (n *Notifier) NotifyControllerUpdated(fromVer, toVer string, success bool)
 }
 
 // NotifyControllerStarted sends a controller startup event.
-func (n *Notifier) NotifyControllerStarted(version string) {
+// details may include self-test summary (e.g., {"selftest_pass": 8, "selftest_warn": 1, "selftest_fail": 0}).
+func (n *Notifier) NotifyControllerStarted(version string, details map[string]interface{}) {
 	n.PushEvent("controller_started", "info",
-		fmt.Sprintf("Controller elindult (%s)", version), nil)
+		fmt.Sprintf("Controller elindult (%s)", version), details)
 }
 
 // NotifyStorageDisconnected sends a drive disconnection event.
@@ -375,6 +384,10 @@ func (n *Notifier) SyncPreferences(email string, enabledEvents []string, cooldow
 	}
 
 	url := n.hubURL + "/api/v1/preferences"
+	if n.debug {
+		n.logger.Printf("[DEBUG] SyncPreferences: url=%s email=%s events=%v cooldown=%dh",
+			url, email, enabledEvents, cooldownHours)
+	}
 	req, err := http.NewRequest("POST", url, bytes.NewReader(jsonData))
 	if err != nil {
 		return fmt.Errorf("request: %w", err)
@@ -393,6 +406,9 @@ func (n *Notifier) SyncPreferences(email string, enabledEvents []string, cooldow
 		return fmt.Errorf("hub hiba (%d): %s", resp.StatusCode, string(body))
 	}
 
+	if n.debug {
+		n.logger.Printf("[DEBUG] SyncPreferences: response HTTP %d", resp.StatusCode)
+	}
 	n.logger.Printf("[INFO] Notification preferences synced to hub: email=%s, events=%v, cooldown=%dh", email, enabledEvents, cooldownHours)
 	return nil
 }