TO and FOR after transitive Verb
Solution 1:
[1] We intend to leave in a month.
[2] A fund intended for emergency use only.
You are right. "Intend" is intransitive in both examples.
In [1] "intend" is a catenative verb with the infinitival clause "to leave in a month" as its catenative complement. "To" is a marker of the infinitival clause.
In [2] the past participle verb "intended" is head of the past participial clause "intended for emergency use only", functioning as modifier of "fund". It's the semantic equivalent of the relative clause in "A fund that is/was intended for emergency use only".