The English word "happy" derives from the word "hap," which originally meant chance, fortune, or luck, and came to mean any sort of event. We still have this meaning in words like happen, happening, happenstance.
Over time "happy" came to mean only good luck, not bad. "Luck" and "fortune" had the same evolution - you can have bad luck or misfortune, but lucky and fortunate mean only good things. So happy came to mean "fortunate."
It took many centuries for "happy" to change from meaning "fortunate" to meaning a person's positive internal emotional state, often but not always caused by external fortunate events.
Nowadays the "fortunate" meaning of "happy" is mostly obsolete, and "happy" refers mostly to the emotional state - the opposite of sad, but less emphatic than joyful.
For several hundred years, though, both meanings of "happy" existed side by side. The Oxford English Dictionary gives the very earliest "emotional state" meaning use as being in 1525, while the "fortunate" meaning was still in use at the end of the 19th century.
When you read translations of Biblical texts - such as the quote from Job ("happy is the man whom God corrects") and the the others in the comments above - keep in mind you are reading material that was either written a century or more ago, or modern material that is strongly influenced by prior translations. So the fact that a translation of Job uses "happy" doesn't necessarily imply that someone corrected by God is experiencing an emotionally pleasurable feeling.
Even though there's still a bit of "good fortune" lingering around the word "happy," that meaning is mostly gone from ordinary use. Yet it seems to me that the translations of "ashrei" as "happy" are more focussed on the "fortunate" meaning of the original texts. So I would vote for translating ashrei as "fortunate" over "happy" unless it's clear that a specific person's inner emotional feelings are intended.