mgmt: handle rib/announce command

This commit adds logic to NFD so it can handle the new Prefix
Announcement protocol, which are commands sent to rib/announce
with Prefix Announcement object in the Application Parameters.

Refs: #4650
Change-Id: I2a306eb2c3eeb638cc789329d998bfa278880ca6
diff --git a/daemon/rib/route.cpp b/daemon/rib/route.cpp
index e7c825f..5011290 100644
--- a/daemon/rib/route.cpp
+++ b/daemon/rib/route.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2023,  Regents of the University of California,
+ * Copyright (c) 2014-2025,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -29,8 +29,6 @@
 
 namespace nfd::rib {
 
-constexpr uint64_t PA_ROUTE_COST = 2048; // cost of route created by prefix announcement
-
 Route::Route() = default;
 
 static time::steady_clock::time_point