fix: gate PezkuwiCheckImmortal on chain identity, not extension presence

Confirmed via on-device logcat trace: approving a multisig operation on
Polkadot Asset Hub failed with "Failed to encode extension CheckMortality"
because isPezkuwi checked for the "AuthorizeCall" signed extension, which
Polkadot Asset Hub also declares - so PezkuwiCheckImmortal's raw DictEnum
value was used there too, and it isn't a valid instance of Polkadot's own
Era type codec. Switched the gate to the existing chain.isPezkuwiChain
(genesis-hash based) check already used for the bizinikiwi signing context
split. Also removes the temporary diagnostic logging added while tracing
this bug and the earlier deep-link routing fix.

app/src/main/res/navigation/split_screen_nav_graph.xml

@@ -847,6 +847,14 @@
             app:popUpTo="@id/balanceDetailFragment"
             app:popUpToInclusive="true" />
 
+        <action
+            android:id="@+id/action_balanceDetailFragment_to_bridgeFlow"
+            app:destination="@id/bridgeFragment"
+            app:enterAnim="@anim/fragment_open_enter"
+            app:exitAnim="@anim/fragment_open_exit"
+            app:popEnterAnim="@anim/fragment_close_enter"
+            app:popExitAnim="@anim/fragment_close_exit" />
+
     </fragment>
 
     <fragment