## Is your feature request related to a problem?

Currently the funnel time to convert query (added in #4947) only allows measuring time it took to a specific step from the one immediately preceding it. However it'd be useful to also bin by the _total_ time to convert – how long it took to complete the funnel (reach the last step) from entering it (reaching the first step).

## Describe the solution you'd like

Right now `ClickhouseFunnelTimeToConvert` uses only `Filter.funnel_to_step`. It should also be able to work with `Filter.funnel_from_step`. If `funnel_from_step` is `0` and `funnel_to_step` is `len(steps)-1`, that'd be the total time to convert.

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

ee/clickhouse/queries/funnels/funnel_time_to_convert.py
bin_count = 90
            bin_count_identifier = str(bin_count)
            bin_count_expression = None
        else:
            
            bin_count_identifier = "bin_count"
            bin_count_expression = f"""
                count() AS sample_count,
                least(60, greatest(3, ceil(cbrt(sample_count)))) AS {bin_count_identifier},
            """
        if not (0 < to_step < len(self._filter.entities)):
            raise ValidationError(
                f'Filter parameter {FUNNEL_TO_STEP} can only be one of {", ".join(map(str, range(1, len(self._filter.entities))))} for time to convert!'
            )
        query = f"""
            WITH
                step_runs AS (
                    {steps_per_person_query}
                ),
                histogram_params AS (
                    -- Binning ensures that each sample belongs to a bin in results
                    -- If bin_count is not a custom number, it's calculated in bin_count_expression
                    SELECT
                        floor(min(step_{to_step}_average_conversion_time)) AS from_seconds,
                        ceil(max(step_{to_step}_average_conversion_time)) AS to_seconds,
                        {bin_count_expression or ""}
                        ceil((to_seconds - from_seconds) / {bin_count_identifier}) AS bin_width_seconds
                    FROM step_runs
                ),
                -- Below CTEs make histogram_params columns available to the query below as straightforward identifiers