Docs: mention that IDs for items and locations can overlap (Archipela…

…goMW#2854)

* Docs: mention that IDs for items and locations can overlap

* Update docs/world api.md

Co-authored-by: Ixrec <ericrhitchcock@gmail.com>

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Co-authored-by: Ixrec <ericrhitchcock@gmail.com>

docs/world api.md

@@ -170,6 +170,7 @@ could also be progress in a research tree, or even something more abstract like
 Each location has a `name` and an `address` (hereafter referred to as an `id`), is placed in a Region, has access rules,
 and has a classification. The name needs to be unique within each game and must not be numeric (must contain least 1
 letter or symbol). The ID needs to be unique across all games, and is best kept in the same range as the item IDs.
+Locations and items can share IDs, so typically a game's locations and items start at the same ID.
 
 World-specific IDs must be in the range 1 to 2<sup>53</sup>-1; IDs ≤ 0 are global and reserved.