Refactor time series events

[Lane]

Changes

<TimeSeriesEventsLayer />

• pull out utility functions and child components from the component body (performance)
• refactor utility functions and function comments (where able)

formatDateString -> formatDateRange

• renamed the formatDateString utility to formatDateRange, because it is for date ranges
• pulled the single date formatter into separate function (so you don't need to pass a date twice when formatting single dates)

Add <EventMarker />

• the event glyph was being used in multiple places, so i created a common component for sharing between components

Add <TimeSeriesEvent />

• created separate component for time series events, so it can be re-used in the tooltip. uses <EventMarker /> for the glyph
• removed extra <Box> elements, should avoid adding empty boxes for spacing.

Use the language store for hardcoded strings

• instead of hardcoding strings, we should use the language config in App.js and the useLang hook.