Suggestion: New API QueryParam: `/game/systems/:symbol/flight-plans` createdAt

[Jonathan B]

The current endpoint for "Get all system flight plans" currently returns every flight that is currently active.

As a suggestion, if we can have an additional parameter to only return flights created since a given TimeStamp, we can potentially reduce this response, and clients can combine it with their existing cache.

Client-side, these calls can potentially get heavier in raw size going forward. The last fetch that I performed for OE and XV returned 35.4k of JSON for 150 flights, so as this list grows any potential to reduce this by some fraction could have some impact if someone is only interested in flights they haven't seen before.

https://api.spacetraders.io/game/systems/OE/flight-plans
content-length: 19825
86 Flights

https://api.spacetraders.io/game/systems/XV/flight-plans
content-length: 15262
66 Flights