Add clear stuck jobs admin feature and simplify worker scheduling

- Add POST /api/admin/settings/clear-stuck-jobs endpoint to clear
  stuck/failed asynq worker jobs from Redis (retry queue, archived,
  orphaned task metadata)
- Add "Clear Stuck Jobs" button to admin settings UI
- Remove TASK_REMINDER_MINUTE config - all jobs now run at minute 0
- Simplify formatCron to only take hour parameter
- Update default notification times to CST-friendly hours

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

cmd/worker/main.go

@@ -2,10 +2,10 @@ package main
 
 import (
 	"context"
+	"fmt"
 	"os"
 	"os/signal"
 	"syscall"
-	"time"
 
 	"github.com/hibiken/asynq"
 	"github.com/rs/zerolog/log"
@@ -105,21 +105,21 @@ func main() {
 	scheduler := asynq.NewScheduler(redisOpt, nil)
 
 	// Schedule task reminder notifications
-	reminderCron := formatCron(cfg.Worker.TaskReminderHour, cfg.Worker.TaskReminderMinute)
+	reminderCron := formatCron(cfg.Worker.TaskReminderHour)
 	if _, err := scheduler.Register(reminderCron, asynq.NewTask(jobs.TypeTaskReminder, nil)); err != nil {
 		log.Fatal().Err(err).Msg("Failed to register task reminder job")
 	}
 	log.Info().Str("cron", reminderCron).Msg("Registered task reminder job")
 
-	// Schedule overdue reminder at 9 AM UTC
-	overdueCron := formatCron(cfg.Worker.OverdueReminderHour, 0)
+	// Schedule overdue reminder
+	overdueCron := formatCron(cfg.Worker.OverdueReminderHour)
 	if _, err := scheduler.Register(overdueCron, asynq.NewTask(jobs.TypeOverdueReminder, nil)); err != nil {
 		log.Fatal().Err(err).Msg("Failed to register overdue reminder job")
 	}
 	log.Info().Str("cron", overdueCron).Msg("Registered overdue reminder job")
 
-	// Schedule daily digest at 11 AM UTC
-	dailyCron := formatCron(cfg.Worker.DailyNotifHour, 0)
+	// Schedule daily digest
+	dailyCron := formatCron(cfg.Worker.DailyNotifHour)
 	if _, err := scheduler.Register(dailyCron, asynq.NewTask(jobs.TypeDailyDigest, nil)); err != nil {
 		log.Fatal().Err(err).Msg("Failed to register daily digest job")
 	}
@@ -154,7 +154,7 @@ func main() {
 	log.Info().Msg("Worker stopped")
 }
 
-// formatCron creates a cron expression for a specific hour and minute (UTC)
-func formatCron(hour, minute int) string {
-	return time.Date(0, 1, 1, hour, minute, 0, 0, time.UTC).Format("4 15 * * *")
+// formatCron creates a cron expression for a specific hour (runs at minute 0)
+func formatCron(hour int) string {
+	return fmt.Sprintf("0 %02d * * *", hour)
 }