It's an object. In English, wh-pronouns are fronted, so the declarative form of this sentence (or the full answer to this) would be 'she is calling [John]'. 'Whom' refers to 'John', the object.

What sort of sweets were they? Perhaps she misinterpreted and thought you were referring to the viscosity. It wasn't Turkish Delight, was it?

These are called quantifiers. Typically, the verb agrees with the quantifier, as it is syntactically the head of the noun phrase.

Also, for a perhaps more authoritative description of Em, En and ø-dashes, see english.stackexchange.com/questions/2116/…

@Peter, in my bolshy opinion, punctuation is just an orthographic representation of intonation and we should use whatever we feel is right, and that there shouldn't be any specific purposes or rules. I recall Em dashes being used by James Joyce as an open quote, though, confusingly, he doesn't use anything for a close quote. Quite difficult to read given our modern use of quote marks. See here: ebooks.adelaide.edu.au/j/joyce/james/j8u/episode1.html, especially the quote beginning "— Thanks, old chap,"

In terms of software dev, you could use 'role', 'portfolio', etc. A persona in this context is essentially what type of user someone is. I.e., the site may behave differently if you're a member versus a guest, so there is a guest persona and a member persona that the devs will consider when building in functionality.

An Em dash would indeed work. You can type an Em dash (—) directly on a mac at least with shift-alt-dash. An En dash is a bit narrower – used to separate a parenthetical statement – which you can type using alt-dash. If you don't like either of those, I'd suggest a comma for the first and a colon for the second. Doesn't need to be a complete sentence to use a comma. Also 'an unprecedented…' elaborates on 'her determination to wed him' and so a colon is just what you want.

Yes, practicing and asking people to let you know if your adverb placement sounds wrong, and why, is the best bet to mastering it. Honestly, most native speakers don't know why things are wrong, and will often say it 'sounds weird'. So don't get too hung up about it. Would you mind accepting my answer by ticking it?

Perhaps 'Externalise'. Although not a noun, but I think it roughly conveys the meaning you intend.

Agree with @YosefBaskin. Why do you specifically want a phrasal verb for this?

I was working on the assumption that OP meant noun when they said noun. I agree that 'research and select...' is also good.