Update profitability colour indicator on strategy tile chart

[kenkunz]

Goal

As an investor evaluating different trading strategies, I want the the colour of the chart shown on strategy tiles to reflect an appropriate metric/indicator for comparing profitability, so that I can make an accurate and informed decision about my investments.

Background

See discord thread for further detais.

@tsorro noted that our best performing strategy is currently red:

The current logic is based on the relative profitability for the timeframe displayed on the chart (normally 90 days, but currently shorter due to the length of time our "unrealised profitability" sampling process has been running).

Questions

1. What alternative metric should be used for selecting red/green profitability direction?

Some possible answers based on data points that are available from the metadata endpoint:

1. Total cumulative unrealised profitability (the value of the last data point on the chart). Data point: summary_statistics. compounding_unrealised_trading_profitability.at(-1)
2. Compounding Annual Growth Rate (CAGR) – as shown on the "Annual return" metric on each strategy tile (for some strategies this is based on backtesting data). Data point: summary_statistics.key_metrics.cagr
3. "Profitability" metric in the key metrics, but we replaced this a while ago with CAGR, so I don't think the intention is to keep using this one anywhere. Data point: summary_statistics.key_metrics.profitability
4. Data point: summary_statistics.profitability_90_days (note: older data point)
5. Data point: summary_statistics.return_all_time (note: older data point)
6. Data point: summary_statistics.return_annualised (note: older data point)

@tsorro recommendation:

From my perspective, I would personally want to see green coloured equity curve when the overall profit is above zero, and red if the profit is below zero.

This would let the user understand that this strategy has been profitable until this point in time even if the visible bit of the curve would be pointing a bit downwards.

(this is metric 1 from the above list).

Resulting profit indicator colours:

Acceptance criteria

tbd