example: Use update_last_seen_unconfirmed in examples

We can update the last seen unconfirmed time for transactions
by calling `update_last_seen_unconfirmed` on the graph update
returned from a blockchain source, passing in the current time,
before applying it to another `TxGraph`.

example-crates/example_esplora/src/main.rs

@@ -189,10 +189,14 @@ fn main() -> anyhow::Result<()> {
             // is reached. It returns a `TxGraph` update (`graph_update`) and a structure that
             // represents the last active spk derivation indices of keychains
             // (`keychain_indices_update`).
-            let (graph_update, last_active_indices) = client
+            let (mut graph_update, last_active_indices) = client
                 .full_scan(keychain_spks, *stop_gap, scan_options.parallel_requests)
                 .context("scanning for transactions")?;
 
+            // We want to keep track of the latest time a transaction was seen unconfirmed.
+            let now = std::time::UNIX_EPOCH.elapsed().unwrap().as_secs();
+            let _ = graph_update.update_last_seen_unconfirmed(now);
+
             let mut graph = graph.lock().expect("mutex must not be poisoned");
             // Because we did a stop gap based scan we are likely to have some updates to our
             // deriviation indices. Usually before a scan you are on a fresh wallet with no
@@ -307,9 +311,13 @@ fn main() -> anyhow::Result<()> {
                 }
             }
 
-            let graph_update =
+            let mut graph_update =
                 client.sync(spks, txids, outpoints, scan_options.parallel_requests)?;
 
+            // Update last seen unconfirmed
+            let now = std::time::UNIX_EPOCH.elapsed().unwrap().as_secs();
+            let _ = graph_update.update_last_seen_unconfirmed(now);
+
             graph.lock().unwrap().apply_update(graph_update)
         }
     };

example-crates/wallet_esplora_async/src/main.rs

@@ -53,9 +53,12 @@ async fn main() -> Result<(), anyhow::Error> {
             (k, k_spks)
         })
         .collect();
-    let (update_graph, last_active_indices) = client
+    let (mut update_graph, last_active_indices) = client
         .full_scan(keychain_spks, STOP_GAP, PARALLEL_REQUESTS)
         .await?;
+
+    let now = std::time::UNIX_EPOCH.elapsed().unwrap().as_secs();
+    let _ = update_graph.update_last_seen_unconfirmed(now);
     let missing_heights = update_graph.missing_heights(wallet.local_chain());
     let chain_update = client.update_local_chain(prev_tip, missing_heights).await?;
     let update = Update {

example-crates/wallet_esplora_blocking/src/main.rs

@@ -53,8 +53,11 @@ fn main() -> Result<(), anyhow::Error> {
         })
         .collect();
 
-    let (update_graph, last_active_indices) =
+    let (mut update_graph, last_active_indices) =
         client.full_scan(keychain_spks, STOP_GAP, PARALLEL_REQUESTS)?;
+
+    let now = std::time::UNIX_EPOCH.elapsed().unwrap().as_secs();
+    let _ = update_graph.update_last_seen_unconfirmed(now);
     let missing_heights = update_graph.missing_heights(wallet.local_chain());
     let chain_update = client.update_local_chain(prev_tip, missing_heights)?;
     let update = Update {