initial refactor in preparation for routing

Signed-off-by: William Casarin <jb55@jb55.com>

src/route.rs

@@ -0,0 +1,7 @@
+use nostrdb::NoteKey;
+
+/// App routing. These describe different places you can go inside Notedeck.
+pub enum Route {
+    ManageAccount,
+    Thread(NoteKey),
+}