Yes and no 
It either means “and that’s the whole thing sorted out”…or it means “after that, it’s all to obvious for words”. But you’re on the right kind of path 
And Fanny’s your Aunt
Can also be added afterwards.
And no, you’re not wrong.
Have you worked out the meanimg of Djelibabi from Pyramids yet?
Don’t worry if you haven’t. It took me a while to work out what Hersheba means.
Americans don’t get the item referenced in the first bit so I expect that’ll be an obscure one.
I’m guessing the second one is hershey bar, which most Brits won’t know about.
I did, but I learned that from Dr. Who.
Oh, it can’t be that obscure – it’s not hard to go from Djelibabi to the prominent merchandise in every Sweet Factory mall candy store.
As for the OP, I’ll add “Yorkie Bar” and Dunnmanifestin to the list.
Like mks57, Morris dancing. I had no clue what they were talking about in that book, whichever one it was, so I had to look it up on the AFP.
OK, I’m getting the gist…
Does Pratchett note the traditional salutation from waitresses, djoiameel?
Believe me, you don’t want to see Morris dancing. Trust me on this one.
Trebor Bassett Jelly Babies.
Ooh I didn’t get the hersheba one. Me silly. I think I mentally put the stress in the wrong place, but, being in Britain
anyway…
How about Imp Y Celyn’s home village of Llamedos? Actually. though, I suppose anyone familiar with Dylan Thomas would get that one.
Not exactly, sultanas are made from green grapes, whereas raisins are made from red ones.
I thought Bjorn Stronginthearm was your uncle! 
Good Omens taught me about firelighters and draft excluders and that the M5’s topography spells out a Satanic invocation.
Every time I need to remember the intricacies of old-style English currency, I go dig out my copy of Good Omens and look at the footnote.
So they’re what we call “golden raisins”?
I coulda sworn there was a Cecil’s column or Staff Report on this, but I couldn’t find it. Here’s a loose translation: There was once an Englishman who got a fat government job. He was not qualified for the post, but his uncle Robert was already a powerful government guy, so he was in. There was a fuss about it, but there he stayed. So, when you say, “and Bob’s your uncle” to mean, “and it’s as good as done,” you’re making a sarcastic reference to that long-ago nepotism.
There’s a US phrase “I’ll be there with bells on,” that refers to making a journey in a horse-drawn wagon or sleigh without any breakdowns. Supposedly, if somebody helped you with repairs, you gave him some some of the bells from your horses. However, I have a feeling Pratchett meant something else.
Bob’s your uncle origin.
I have learned that British parody can almost make me laugh until I need someone to “tip the wee out of my shoe”.
I haven’t the foggiest idea if the word “twee” is a real English word, but I have learned it well and use it every chance I get. As in: “If I catch you being twee again I will knot your arms behind your head.”
I have learned the importance of kicking the hell out of cowardly Johnny Klatchian for no very good reason…no, wait…on second thought, that’s just more of the crap our president keeps spewing.
I have learned that a fag end can be re-smoked near-indefinitely if one stores it behind one’s ear.
I have learned what a “fry-up” is, about “burnt crunchy bits” as they relate to both breakfast and treacle, and what treacle is in the first place.
I have learned what a “verruca” is (a wart), what “going spare” means (also “going round the bend” and “going totally Librarian poo”), and that shopping carts are “trolleys”.
Buggerit! Millennium hand and shrimp!
I’m still trying to figure out just what a “gel” is. And how it’s different from a “gal”.