feat(channel-monitor): aggregate history to daily rollups + soft delete

明细只保留 1 天，超过 1 天聚合到新表 channel_monitor_daily_rollups（按
monitor_id/model/bucket_date 维度），聚合保留 30 天。两张表都用 SoftDeleteMixin
软删除（DELETE 自动改为 UPDATE deleted_at = NOW()）。

聚合 + 清理任务由 OpsCleanupService 的 cron 统一调度，与运维监控的清理共享
schedule（默认 0 2 * * *）和 leader lock。ChannelMonitorRunner 的 cleanupLoop
被移除，只保留 dueCheckLoop。

读取路径 ComputeAvailability* 改为 UNION 明细（今天 deleted_at IS NULL）+
聚合（过去 windowDays 天 deleted_at IS NULL），SUM(ok)/SUM(total) 自然加权
计算可用率，AVG latency 用 SUM(sum_latency_ms)/SUM(count_latency)。

watermark 表 channel_monitor_aggregation_watermark 单行（id=1），记录
last_aggregated_date，重启后从该日期 +1 继续聚合，首次为 nil 则从
today - 30d 开始回填，单次最多 35 天上限避免长事务。

raw SQL 的 ListLatestPerModel / ListLatestForMonitorIDs / ListRecentHistoryForMonitors
都补上 deleted_at IS NULL 过滤（SoftDeleteMixin interceptor 只对 ent query 生效）。

bump version to 0.1.114.28

GroupBadge 在 MonitorKeyPickerDialog 中复用平台主题色 + 倍率/专属倍率
（顺手优化）。

backend/ent/channelmonitorhistory.go

@@ -18,6 +18,8 @@ type ChannelMonitorHistory struct {
 	config `json:"-"`
 	// ID of the ent.
 	ID int64 `json:"id,omitempty"`
+	// DeletedAt holds the value of the "deleted_at" field.
+	DeletedAt *time.Time `json:"deleted_at,omitempty"`
 	// MonitorID holds the value of the "monitor_id" field.
 	MonitorID int64 `json:"monitor_id,omitempty"`
 	// Model holds the value of the "model" field.
@@ -67,7 +69,7 @@ func (*ChannelMonitorHistory) scanValues(columns []string) ([]any, error) {
 			values[i] = new(sql.NullInt64)
 		case channelmonitorhistory.FieldModel, channelmonitorhistory.FieldStatus, channelmonitorhistory.FieldMessage:
 			values[i] = new(sql.NullString)
-		case channelmonitorhistory.FieldCheckedAt:
+		case channelmonitorhistory.FieldDeletedAt, channelmonitorhistory.FieldCheckedAt:
 			values[i] = new(sql.NullTime)
 		default:
 			values[i] = new(sql.UnknownType)
@@ -90,6 +92,13 @@ func (_m *ChannelMonitorHistory) assignValues(columns []string, values []any) er
 				return fmt.Errorf("unexpected type %T for field id", value)
 			}
 			_m.ID = int64(value.Int64)
+		case channelmonitorhistory.FieldDeletedAt:
+			if value, ok := values[i].(*sql.NullTime); !ok {
+				return fmt.Errorf("unexpected type %T for field deleted_at", values[i])
+			} else if value.Valid {
+				_m.DeletedAt = new(time.Time)
+				*_m.DeletedAt = value.Time
+			}
 		case channelmonitorhistory.FieldMonitorID:
 			if value, ok := values[i].(*sql.NullInt64); !ok {
 				return fmt.Errorf("unexpected type %T for field monitor_id", values[i])
@@ -175,6 +184,11 @@ func (_m *ChannelMonitorHistory) String() string {
 	var builder strings.Builder
 	builder.WriteString("ChannelMonitorHistory(")
 	builder.WriteString(fmt.Sprintf("id=%v, ", _m.ID))
+	if v := _m.DeletedAt; v != nil {
+		builder.WriteString("deleted_at=")
+		builder.WriteString(v.Format(time.ANSIC))
+	}
+	builder.WriteString(", ")
 	builder.WriteString("monitor_id=")
 	builder.WriteString(fmt.Sprintf("%v", _m.MonitorID))
 	builder.WriteString(", ")