melee weapons are valid for an entire campaign - unless it was spawned by a plugin.. in which case, that plugin should be precaching the model.
as far as when a map starts:
round_start fires usually 2 times, then the survivor bots spawn (player_first_spawn), then the player_takeover_bot (or however it is spelled) is fired as each survivor loads in.
pretty sure player_entered_start_area doesn't fire when they are spawned inside the start area, only after they leave and re-enter.
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