refactor(plugin): rename detection_interval_seconds → detection_interval_minutes (#9366)

Minutes is the natural granularity for detection cadence — every
production handler already set the seconds field to a 60-multiple
(17*60, 30*60, 3600, 24*60*60). Switching to minutes drops the *60
arithmetic and matches the unit conventions used elsewhere in the
plugin worker forms.

- Proto: AdminRuntimeDefaults + AdminRuntimeConfig.detection_interval_*
  field renamed.
- Helpers: durationFromMinutes / minutesFromDuration alongside the
  existing seconds variants in plugin_scheduler.go.
- Handlers: vacuum, ec_balance, balance, erasure_coding, iceberg,
  admin_script, s3_lifecycle now declare DetectionIntervalMinutes.
- Admin: scheduler_status + types + UI templ + plugin_api.go pass
  through the new field; UI label and table cells switch to "min".

weed/worker/tasks/balance/plugin_handler.go

@@ -220,7 +220,7 @@ func (h *VolumeBalanceHandler) Descriptor() *plugin_pb.JobTypeDescriptor {
 		},
 		AdminRuntimeDefaults: &plugin_pb.AdminRuntimeDefaults{
 			Enabled:                       true,
-			DetectionIntervalSeconds:      30 * 60,
+			DetectionIntervalMinutes:      30,
 			DetectionTimeoutSeconds:       120,
 			MaxJobsPerDetection:           100,
 			GlobalExecutionConcurrency:    16,

weed/worker/tasks/ec_balance/plugin_handler.go

@@ -159,7 +159,7 @@ func (h *ECBalanceHandler) Descriptor() *plugin_pb.JobTypeDescriptor {
 		},
 		AdminRuntimeDefaults: &plugin_pb.AdminRuntimeDefaults{
 			Enabled:                       true,
-			DetectionIntervalSeconds:      60 * 30,
+			DetectionIntervalMinutes:      30,
 			DetectionTimeoutSeconds:       300,
 			MaxJobsPerDetection:           500,
 			GlobalExecutionConcurrency:    16,

weed/worker/tasks/erasure_coding/plugin_handler.go

@@ -158,7 +158,7 @@ func (h *ErasureCodingHandler) Descriptor() *plugin_pb.JobTypeDescriptor {
 		},
 		AdminRuntimeDefaults: &plugin_pb.AdminRuntimeDefaults{
 			Enabled:                       true,
-			DetectionIntervalSeconds:      17 * 60,
+			DetectionIntervalMinutes:      17,
 			DetectionTimeoutSeconds:       300,
 			MaxJobsPerDetection:           500,
 			GlobalExecutionConcurrency:    16,

weed/worker/tasks/iceberg/handler.go

@@ -324,7 +324,7 @@ func (h *Handler) Descriptor() *plugin_pb.JobTypeDescriptor {
 		},
 		AdminRuntimeDefaults: &plugin_pb.AdminRuntimeDefaults{
 			Enabled:                       false, // disabled by default
-			DetectionIntervalSeconds:      3600,  // 1 hour
+			DetectionIntervalMinutes:      60, // 1 hour
 			DetectionTimeoutSeconds:       300,
 			MaxJobsPerDetection:           100,
 			GlobalExecutionConcurrency:    4,
@@ -374,7 +374,7 @@ func (h *Handler) Detect(ctx context.Context, request *plugin_pb.RunDetectionReq
 		return fmt.Errorf("invalid where config: %w", err)
 	}
 
-	// Detection interval is managed by the scheduler via AdminRuntimeDefaults.DetectionIntervalSeconds.
+	// Detection interval is managed by the scheduler via AdminRuntimeDefaults.DetectionIntervalMinutes.
 
 	// Get filer addresses from cluster context
 	filerAddresses := make([]string, 0)

weed/worker/tasks/s3_lifecycle/handler.go

@@ -141,7 +141,7 @@ func (h *Handler) Descriptor() *plugin_pb.JobTypeDescriptor {
 			},
 		},
 		AdminRuntimeDefaults: &plugin_pb.AdminRuntimeDefaults{
-			DetectionIntervalSeconds: 24 * 60 * 60, // daily
+			DetectionIntervalMinutes: 24 * 60, // daily
 			DetectionTimeoutSeconds:  60,
 			MaxJobsPerDetection:      1,
 		},

weed/worker/tasks/vacuum/plugin_handler.go

@@ -178,7 +178,7 @@ func (h *VacuumHandler) Descriptor() *plugin_pb.JobTypeDescriptor {
 		},
 		AdminRuntimeDefaults: &plugin_pb.AdminRuntimeDefaults{
 			Enabled:                       true,
-			DetectionIntervalSeconds:      17 * 60,
+			DetectionIntervalMinutes:      17,
 			DetectionTimeoutSeconds:       120,
 			MaxJobsPerDetection:           200,
 			GlobalExecutionConcurrency:    16,