Who is the author who first described the biblical metanarrative of scripture as Creation, Fall, Redemption -- and some include Restoration or New Creation?
While creation and redemption were early Christian/biblical concepts, the notion of a "Fall" draws heavily from Platonism and Neoplatonism. Pushing all three together into a narrative is probably easiest to attribute to Augustine, the great importer of Neoplatonist themes into Christian doctrine, but let's unpack each of the three.
Obviously the creation narratives in the first three chapters of Genesis have been interpreted in various ways throughout the history of Jewish and Christian thought. However, these differing interpretations usually disagree on the how of creation, (1) (2) (3) (4) not the cause of creation. (5) (6) (7) For example, Christian thinkers may disagree on the time span of creation (literal six days?), but all Christian theologians agree that God is ultimately creator. (8) (9)
This is a bit tricky to answer in the context of this question and we will need to come back to it afterward for a fuller answer. Like the doctrine of creation, redemption has had many differing interpretations. It's probably best categorized under the doctrine of soteriology which answers the question: How does God save? Biblical concepts inside this doctrine include topics like redemption, reconciliation, propitiation, forgiveness, and justification. (10)
Depending on the period of Christian history and the theologian, the way we approach soteriology can be radically different, but indebted to Jewish thought, the early church always had a concept that God is the one who "saves". (11) (12)
Here's the missing piece of the puzzle that ties the narrative together. Many modern Christians have lumped concepts like Adam's first sin, the fall, and original sin together to mean the same thing. If that's you, you probably owe it to a modified version of St. Augustine's teaching on the issue. But that deserves a bit of unpacking. First, let's talk about the fall.
The fall really isn't a biblical concept. That language of descent doesn't manifest itself in the garden narrative or in the early Christian writings. If anything, the paradigm wasn't a vertical one, but a horizontal one: inclusion vs exclusion: Adam and Eve were excluded from the garden, Gehenna -- often translated as "hell" in English -- is literally a valley outside the city of Jerusalem. (13) (14) (15)
In fact, the concept of the fall, really becomes cemented in Christian doctrine because of Augustine. His project merges Plotinus, the great neoplatonist thinker, with the Christian tradition. In the Phaedrus, Plato describes the fall of the immortal soul in heaven, which Plotinius expands and orders into a systematic doctrine. (16) (17) (18)
In order to go any further, it's time to get some technical terminology out of the way. First let's start with the difference between original sin and first sin (or Adam's sin). The first sin is a reference to the Garden of Eden. Literally, it's when Adam and Eve ate from the tree. Original sin is also a concept that comes from Augustine, and it is a sharing of all humanity in the first sin. For Augustine, when Adam ate from the tree, all humanity shared in that sin in mass condemnation. (19) (20) (21)
What's going on here? Well, the church hadn't yet condemned the doctrine of the preexistence of souls in Augustine's time, but it was not common doctrine. Humans are not immortal, and therefore we need a beginning. For most Christians, our souls are created like the rest of created things and there was a time when "we were not." (22)
So Augustine can't use the concept of the fall like the platonists do. Individually, for Augustine, we don't fall into our bodies from an eternal, heavenly state. Instead, the entire human race fell into original sin during that first sin of Adam. (23) The consequence, for Augustine, is a perversion of our "will" or desire. Humans are now in need of repairing or mending this broken will. (24) (25)
In a famous quote from Augustine, he says, "My weight is my love." (26) What he means is that by loving higher things, our weight becomes lighter (like the ancient element of fire) and we tend toward heaven. By loving lower things, I become heavier and tend toward lower existence (like the ancient element of earth). Tying it together, redemption becomes the healing of our will or desire. When God heals us, we become capable of loving God, which draws our souls toward heaven.
Is this still the way all theologians view this narrative of creation, fall, and redemption? No. Throughout the history of the church, theologians have rethought these concepts. It's not really fashionable (or believable) to base a modern theology on Neoplatonism, but Augustine's impact can still be felt. Even thinkers who reject Platonism will still use concepts like Original Sin and the Fall, but interpret them in different ways.
I found this article:
Smither, EL (2014). Augustine on redemption in Genesis 1–3. Verbum et Ecclesia; Vol 35, No 1. doi: 10.4102/ve.v35i1.1315
Which says this:
"In his Genesis works, Augustine was primarily concerned with clarifying the doctrine of creation and, relatively speaking, had far less to say about redemption"
Which seems to strongly imply that Augustine at least had a creation, fall, redemption view implicit in his understanding of scripture. Whether he explicitly described it this way I don't know, nor whether he was the first to say/use it.