feat(jellyfish-api-core): Add account getPendingFutureSwaps RPC for dfip2203 futures

docs/node/CATEGORIES/08-account.md

@@ -490,4 +490,23 @@ interface UTXO {
   txid: string
   vout: number
 }
+```
+## getPendingFutureSwaps
+
+Get specific pending futures.
+
+```ts title="client.account.getPendingFutureSwaps()"
+interface account {
+  getPendingFutureSwaps (address: string): Promise<GetFutureInfo>
+}
+
+interface GetFutureInfo {
+  owner: string
+  values: FutureData[]
+}
+
+interface FutureData {
+  source: string // eg: '1.234@DUSD'
+  destination: string
+}
 ```