[Tagging] Tagging Free Water for cafés, bars, restaurant

[marc marc]

> free_water:container = <bring_your_own, provided>

bring_your_own is very explicit.
but "provided" or "establishment" is ambiguous.
from my experience, drinking a free glass of water in a cafe is not at
all the same as receiving a container filled with water (I have never
encountered this case).
so the choice should be between values like your_own_takeaway_container
<> on_site