I'm looking at coordination strategies in the languages of the world and I wonder if all languages have a distinction between conjunction and disjunction.
Why do you think any language distinguishes. Syntacticians generally use the term "conjunction" to refer to a class of constructions including both "and" and "or", because both of these work the same way, grammatically. They both connect constituents of the same type and create a new constituent of that same type. For instance, "Benny likes halibut or despises smelt" has a verb phrase, "likes halibut or despises smelt" which has two constituents of that same type conjoined by "or", the verb phrase "likes halibut" and the verb phrase "despises smelt". If we exchange "or" for "and", we get a construction of exactly the same type.