fix: clear RootAlphaDividendsPerSubnet on network removal

RootAlphaDividendsPerSubnet is not cleaned up when a subnet is
dissolved. Since netuids are recycled (subnet.rs:178-186), stale root
dividend entries from the old subnet persist and become visible to the
new subnet, potentially affecting run_coinbase dividend calculations.

Add clear_prefix for RootAlphaDividendsPerSubnet alongside the existing
AlphaDividendsPerSubnet cleanup in remove_network.

Closes #1867

Author: plind-junior

pallets/subtensor/src/coinbase/root.rs

@@ -368,6 +368,9 @@ impl<T: Config> Pallet<T> {
         let _ = NeuronCertificates::<T>::clear_prefix(netuid, u32::MAX, None);
         let _ = Prometheus::<T>::clear_prefix(netuid, u32::MAX, None);
         let _ = AlphaDividendsPerSubnet::<T>::clear_prefix(netuid, u32::MAX, None);
+        let _ = RootAlphaDividendsPerSubnet::<T>::clear_prefix(netuid, u32::MAX, None);
+        let _ = VotingPower::<T>::clear_prefix(netuid, u32::MAX, None);
+        let _ = RootClaimed::<T>::clear_prefix((netuid,), u32::MAX, None);
         let _ = PendingChildKeys::<T>::clear_prefix(netuid, u32::MAX, None);
         let _ = AssociatedEvmAddress::<T>::clear_prefix(netuid, u32::MAX, None);
 

pallets/subtensor/src/tests/networks.rs

@@ -2632,3 +2632,76 @@ fn register_network_non_associated_hotkey_does_not_withdraw_or_write_owner_alpha
         );
     });
 }
+
+#[test]
+fn dissolve_network_clears_root_alpha_dividends() {
+    new_test_ext(0).execute_with(|| {
+        let cold = U256::from(1);
+        let hot = U256::from(2);
+        let net = add_dynamic_network(&hot, &cold);
+
+        // Insert some root alpha dividend data for this subnet.
+        RootAlphaDividendsPerSubnet::<Test>::insert(net, hot, AlphaBalance::from(1000));
+        assert!(RootAlphaDividendsPerSubnet::<Test>::contains_key(net, hot));
+
+        // Dissolve the network.
+        SubtensorModule::set_subnet_locked_balance(net, TaoBalance::from(0));
+        SubnetTAO::<Test>::insert(net, TaoBalance::from(0));
+        Emission::<Test>::insert(net, Vec::<AlphaBalance>::new());
+        assert_ok!(SubtensorModule::do_dissolve_network(net));
+
+        // RootAlphaDividendsPerSubnet should be cleared.
+        assert!(
+            !RootAlphaDividendsPerSubnet::<Test>::contains_key(net, hot),
+            "RootAlphaDividendsPerSubnet not cleaned up after network removal"
+        );
+    });
+}
+
+#[test]
+fn dissolve_network_clears_voting_power() {
+    new_test_ext(0).execute_with(|| {
+        let cold = U256::from(1);
+        let hot = U256::from(2);
+        let net = add_dynamic_network(&hot, &cold);
+
+        // Insert voting power for a validator on this subnet.
+        VotingPower::<Test>::insert(net, hot, 9999u64);
+        assert!(VotingPower::<Test>::contains_key(net, hot));
+
+        // Dissolve the network.
+        SubtensorModule::set_subnet_locked_balance(net, TaoBalance::from(0));
+        SubnetTAO::<Test>::insert(net, TaoBalance::from(0));
+        Emission::<Test>::insert(net, Vec::<AlphaBalance>::new());
+        assert_ok!(SubtensorModule::do_dissolve_network(net));
+
+        assert!(
+            !VotingPower::<Test>::contains_key(net, hot),
+            "VotingPower not cleaned up after network removal"
+        );
+    });
+}
+
+#[test]
+fn dissolve_network_clears_root_claimed() {
+    new_test_ext(0).execute_with(|| {
+        let cold = U256::from(1);
+        let hot = U256::from(2);
+        let net = add_dynamic_network(&hot, &cold);
+
+        // Simulate a recorded root claim for this subnet.
+        RootClaimed::<Test>::insert((net, hot, cold), 500u128);
+        assert!(RootClaimed::<Test>::contains_key((net, hot, cold)));
+
+        // Dissolve the network.
+        SubtensorModule::set_subnet_locked_balance(net, TaoBalance::from(0));
+        SubnetTAO::<Test>::insert(net, TaoBalance::from(0));
+        Emission::<Test>::insert(net, Vec::<AlphaBalance>::new());
+        assert_ok!(SubtensorModule::do_dissolve_network(net));
+
+        assert!(
+            !RootClaimed::<Test>::contains_key((net, hot, cold)),
+            "RootClaimed not cleaned up after network removal"
+        );
+    });
+}