## Is your feature request related to a problem?

There's only 2 files where we use pandas, but pandas is 49MB and numpy is another 86MB, slowing down builds massively.

## Describe the solution you'd like

Replace pandas with a pure SQL/Python solution in
- posthog/queries/trends.py
- posthog/queries/sessions.py

Both of those have equivalent examples in Clickhouse (ee/clickhouse) that don't use Pandas.

## Describe alternatives you've considered

Continue using Pandas and clogging builds

## Additional context



#### *Thank you* for your feature request – we love each and every one!

posthog/queries/trends.py
serialized_data = []
        serialized: Dict[str, Any] = {
            "action": entity.to_dict(),
            "label": entity.name,
            "count": 0,
            "data": [],
            "labels": [],
            "days": [],
        }
        for queried_metric in result:
            serialized_copy = copy.deepcopy(serialized)
            serialized_copy.update(queried_metric)
            serialized_data.append(serialized_copy)
        return serialized_data
    def _handle_cumulative(self, entity_metrics: List) -> List[Dict[str, Any]]: