It doesn’t come from Koheles 10:19 but is a self-admitted translation of secular “joie de vivre” from French (the same way Brisker “Talmudic” concepts come from silly goyish philosophy). And in the same breath, mussarnikehs point out there is no special “mitzvah” to be happy, as many Breslovers (mis)interpret Rabbi Nachman’s Likutei Moharan 2:24…
There is nothing Jewish about Simchas Chaim.
Wikipedia has it right. Under “origins and development”, they explain:
Casual use of the phrase in French can be dated back at least as far as Fénelon in the late 17th century, but it was only brought into literary prominence in the 19th century…
Thereafter, it took on increasing weight as a mode of life, evolving at times almost into a secular religion in the early 20th century; and subsequently fed into Lacanian emphasis on “a jouissance beyond the pleasure principle” in the latter half of the century – a time when its emphasis on enthusiasm, energy and spontaneity gave it a global prominence with the rise of hippie culture.
We have written about other false Mussar concepts in the past.
There is even a “Simchas Hachaim Foundation” for publishing Rabbi Avigdor Miller…
Note: This is not to comment on the Jewish approach to happiness.