fix(repeater): feed each bridge every pre-dedup flood copy

A bridge's return-path teacher can only pick the best-received route if it
sees every copy of a flood reply. It does not: the router hands a bridge
only the first copy, later ones being dropped by the engine's seen-table,
and the pre-dedup firehose lives on the dispatcher, which the bridge does
not own. So the teacher always taught from the first-arrived route, which on
a live mesh is routinely the worst one -- observed here, four copies of one
login reply landed over ~1.8s and the teach went out 0.4s in, embedding the
marginal first route.

Subscribe each bridge's note_flood_copy to the dispatcher's raw packet
subscribers at both bridge-creation sites, next to the existing region_map
handoff.

repeater/main.py

@@ -850,6 +850,15 @@ class RepeaterDaemon:
                 # its own flood replies to the region the request arrived under.
                 bridge.region_map = self._region_map
 
+                # Feed this bridge every pre-dedup copy of a flood reply so its
+                # return-path teacher can pick the best-received route rather than
+                # the first-arrived one. The router hands a bridge only the first
+                # copy (later ones are dropped by the engine's seen-table) and the
+                # pre-dedup firehose lives on the dispatcher, which the bridge does
+                # not own -- so the host has to wire it.
+                if self.dispatcher:
+                    self.dispatcher.add_raw_packet_subscriber(bridge.note_flood_copy)
+
                 # Restore persisted state (contacts/channels/messages) from SQLite.
                 # Raises CompanionStateLoadError instead of continuing with an
                 # empty store when persisted rows exist but cannot be loaded.
@@ -1088,6 +1097,15 @@ class RepeaterDaemon:
         # re-scopes its flood replies to the region the request arrived under.
         bridge.region_map = self._region_map
 
+        # Feed this bridge every pre-dedup copy of a flood reply so its
+        # return-path teacher can pick the best-received route rather than
+        # the first-arrived one. The router hands a bridge only the first
+        # copy (later ones are dropped by the engine's seen-table) and the
+        # pre-dedup firehose lives on the dispatcher, which the bridge does
+        # not own -- so the host has to wire it.
+        if self.dispatcher:
+            self.dispatcher.add_raw_packet_subscriber(bridge.note_flood_copy)
+
         # Restore persisted state; raises CompanionStateLoadError when persisted
         # rows exist but cannot be loaded (hot-reload callers surface the error).
         if sqlite_handler: