Name for "you're being X" vs "you're x"

• You're (being) mean / honest / generous

Note, first of all, that mean, honest, and generous are all adjectives describing human behavior. That's a very specialized sense; most adjectives aren't like that, and can't occur after is being instead of is. (In what follows, ungrammatical sentences are marked with an *asterisk)

• *She's being tall / purple / dead / cubical / 4-dimensional / upstairs.

This is the Progressive construction (some form of be, followed immediately by the -ing form of the next verb in the chain). It has some restrictions; most important is that it only works for active predicates.

Active in this context doesn't mean 'Not Passive', but rather 'Not a State'; it means there's an act involved in the meaning. The term for 'Not Active' is Stative, and it can apply to any predicate. (There are several types of Active and of Stative predicates, but I won't get into that here.)

Second, not all X's are adjectives. Predicate nouns, as well as prepositional phrases, can follow be, and they are even less likely to be active behavioral predicates than adjectives are.

• *It's being a doctor / hand lotion / 3 trombones
• *She's being in trouble / over him / on page 39

though they do occur

• He's being an idiot.
• She's being over the top again.

whenever the predicate involves some description or characterization of human behavior, since behavior involves change and motion, and the progressive is good for handling those.

Third, these are all behavioral active predicate adjectives. Most adjectives describe states, not actions, though behavioral adjectives are very, very common, because mostly what people talk about is other people.

So, to proceed to the question, no, there's no special name for expressions like that. They can be described, and when both You're X and You're being X are grammatical (in a vast minority of the X's), the one with being means 'acting like X' at the moment, whereas the one without being means 'X is a part or permanent characteristic of you'. It's like the Spanish difference between

• Estas guapo 'You look handsome.'
• Eres guapo 'You are handsome'.