Add public GET /v1/whitelist/pubkeys for active subscriber pubkeys

Expose JSON array of hex pubkeys backed by ListActivePubkeys query.
Includes OpenAPI documentation and integration tests.

Made-with: Love

internal/http/handlers/users.go

@@ -61,3 +61,12 @@ func (h *Users) Get(w http.ResponseWriter, r *http.Request) {
 	}
 	WriteJSON(w, http.StatusOK, resp)
 }
+
+func (h *Users) ListWhitelistedPubkeys(w http.ResponseWriter, r *http.Request) {
+	pubkeys, err := h.Users.Repo().ListActivePubkeys(r.Context())
+	if err != nil {
+		WriteError(w, http.StatusInternalServerError, "InternalError", err.Error())
+		return
+	}
+	WriteJSON(w, http.StatusOK, pubkeys)
+}