fix: Convert vendor/pezkuwi-subxt from submodule to regular directory

vendor/pezkuwi-subxt/subxt/examples/storage_iterating.rs

@@ -0,0 +1,42 @@
+#![allow(missing_docs)]
+use subxt::ext::futures::StreamExt;
+use subxt::{OnlineClient, PolkadotConfig};
+
+// Generate an interface that we can use from the node's metadata.
+#[subxt::subxt(runtime_metadata_path = "../artifacts/polkadot_metadata_small.scale")]
+pub mod polkadot {}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Create a new API client, configured to talk to Polkadot nodes.
+    let api = OnlineClient::<PolkadotConfig>::new().await?;
+
+    // Build a storage query to access account information. Same as if we were
+    // fetching a single value from this entry.
+    let storage_query = polkadot::storage().system().account();
+
+    // Use that query to access a storage entry, iterate over it and decode values.
+    let client_at = api.storage().at_latest().await?;
+
+    // We provide an empty tuple when iterating. If the storage entry had been an N map with
+    // multiple keys, then we could provide any prefix of those keys to iterate over. This is
+    // statically type checked, so only a valid number/type of keys in the tuple is accepted.
+    let mut values = client_at.entry(storage_query)?.iter(()).await?;
+
+    while let Some(kv) = values.next().await {
+        let kv = kv?;
+
+        // The key decodes into the type that the static address knows about, in this case a
+        // tuple of one entry, because the only part of the key that we can decode is the
+        // AccountId32 for each user.
+        let (account_id32,) = kv.key()?.decode()?;
+
+        // The value decodes into a statically generated type which holds account information.
+        let value = kv.value().decode()?;
+
+        let value_data = value.data;
+        println!("{account_id32}:\n  {value_data:?}");
+    }
+
+    Ok(())
+}