docs: release note for chanstate Store consumer migration

Add a sibling bullet under the existing "Native SQL migration of the
channel state and switch data" heading, covering the consumer-side
swap that pairs with the interface introduced in #10777.

Author: ziggie1984

docs/release-notes/release-notes-0.22.0.md

@@ -56,6 +56,12 @@
     interface](https://github.com/lightningnetwork/lnd/pull/10777) as the
     persistence contract for the channel-state subsystem, decoupling
     consumers from `*channeldb.ChannelStateDB` ahead of the SQL migration.
+  * Switch channel-state consumers (`server`, `lnrpc`, `funding`, `peer`,
+    `contractcourt`, `channelnotifier`, and the channel restore path)
+    over to the [`chanstate.Store`
+    interface](https://github.com/lightningnetwork/lnd/pull/10790),
+    replacing direct `*channeldb.ChannelStateDB` dependencies so the
+    upcoming KV/SQL store implementations can be swapped in transparently.
 
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