[Feature request] Allow Mission without specifying begin and end in types.py

[qianyi-sun]

Proposal

In current implementation, we have Mission that allows both begin and end point and EndlessMission that allows only specifying begin point for the mission. In Mission(), if we could allow begin=None and end=None or begin=auto() and end=auto(), then EndlessMission might be no longer necessary, like:

# EndlessMission can become this
mission = types.Mission(route=Route(begin=(...), end=auto()), ...)

and,

# new implementation that allows specifying end point only
mission = types.Mission(route=Route(begin=auto(), end=(...)), entry_tactic=....)

Motivation

For some use case such as hijacking offline dataset history vehicles as agent(s), sometimes it would be useful to assign the agent(s) a different end point of interest, instead of using the original trajectory (i.e., original both begin and end). Therefore allowing a mission that only specifying end point and could be available (set begin=auto() and specify an end point in the mission).

Alternatives

Alternatively, implement a new mission type like DestinationMission in types.py that allows users to create missions without specifying start point (similiar to the EndlessMission interface but just the opposite) and EndlessMission remains unchanged, such that:

mission = types.DestinationMission(end=(....), ...)

Additional context

No response