feat: add scoped alpha sync and local self-correlation

backend/app/worldquant.py

@@ -257,20 +257,25 @@ class WqClient:
                 errors[key] = str(exc)
         return usage_snapshot(data, errors)
 
-    async def alphas(self, submission, hidden, offset, before):
+    async def alphas(self, submission, hidden, offset, before, *, date_from=None, date_to=None):
         # Cover every platform stage; submitted records are not assumed to be OS only.
         status_key = "status" if submission == "UNSUBMITTED" else "status!"
-        return await self.get(
-            "/users/self/alphas",
-            {
-                status_key: "UNSUBMITTED",
-                "hidden": str(hidden).lower(),
-                "limit": 100,
-                "offset": offset,
-                "order": "dateCreated",
-                "dateCreated<": before,
-            },
-        )
+        params = {
+            status_key: "UNSUBMITTED",
+            "hidden": str(hidden).lower(),
+            "limit": 100,
+            "offset": offset,
+            "order": "dateCreated",
+            "dateCreated<": before,
+        }
+        if date_from is not None and date_to is not None:
+            # Daily intervals are [UTC midnight, next midnight). Submitted dates
+            # use the actual submission time, independently of creation or stage.
+            field = "dateCreated" if submission == "UNSUBMITTED" else "dateSubmitted"
+            params.update({f"{field}>=": date_from, f"{field}<": date_to, "order": field})
+            if field == "dateCreated":
+                params["dateCreated<"] = min(before, date_to)
+        return await self.get("/users/self/alphas", params)
 
     async def alpha(self, alpha_id):
         return await self.get(f"/alphas/{alpha_id}")