logs: add some log to fix scheduling errors

backend/internal/scheduler/scheduler.go

@@ -3,6 +3,7 @@ package scheduler
 import (
 	"context"
 	"fmt"
+	"sync"
 
 	"github.com/robfig/cron/v3"
 	"github.com/tradarr/backend/internal/ai"
@@ -16,6 +17,7 @@ type Scheduler struct {
 	pipeline *ai.Pipeline
 	repo     *models.Repository
 	entryIDs []cron.EntryID
+	running  sync.Mutex
 }
 
 func New(registry *scraper.Registry, pipeline *ai.Pipeline, repo *models.Repository) *Scheduler {
@@ -78,6 +80,17 @@ func (s *Scheduler) loadSchedule() error {
 }
 
 func (s *Scheduler) run() {
+	if !s.running.TryLock() {
+		fmt.Println("scheduler: previous cycle still running, skipping")
+		return
+	}
+	defer s.running.Unlock()
+	defer func() {
+		if r := recover(); r != nil {
+			fmt.Printf("scheduler: panic recovered: %v\n", r)
+		}
+	}()
+
 	fmt.Println("scheduler: starting scraping cycle")
 	if err := s.registry.RunAll(); err != nil {
 		fmt.Printf("scheduler scrape error: %v\n", err)
@@ -87,4 +100,5 @@ func (s *Scheduler) run() {
 	if err := s.pipeline.GenerateForAll(context.Background()); err != nil {
 		fmt.Printf("scheduler summary error: %v\n", err)
 	}
+	fmt.Println("scheduler: cycle complete")
 }