Add contract instance to ledger entry fetch (#2269)

### What

this pr is based off of #2012 

closes #2273

Updates the `ledger entry fetch` command to allow for returning the
contract instance ledger entry by adding an `--instance` option which
will include the contract instance ledger entry to the list of keys
being fetched.

`cargo run ledger entry fetch contract-data --contract hello-world
--network local --instance`

### Why

This way we are able to more easily fetch a contract wasm hash based on
it's contract id/alias.

### Known limitations

[TODO or N/A]

---------

Co-authored-by: Gleb <gleb@stellar.org>
Co-authored-by: Jane Wang <jane.wang@stellar.org>
Co-authored-by: Leigh <351529+leighmcculloch@users.noreply.github.com>

Author: 4 people

cmd/soroban-cli/src/commands/ledger/entry/fetch/contract_data.rs

@@ -24,12 +24,16 @@ pub struct Cmd {
     pub durability: Durability,
 
     /// Storage key (symbols only)
-    #[arg(long = "key", required_unless_present = "key_xdr")]
+    #[arg(long = "key", required_unless_present_any = vec!("key_xdr", "instance"))]
     pub key: Option<Vec<String>>,
 
     /// Storage key (base64-encoded XDR)
-    #[arg(long = "key-xdr", required_unless_present = "key")]
+    #[arg(long = "key-xdr", required_unless_present_any = vec!("key", "instance"))]
     pub key_xdr: Option<Vec<String>>,
+
+    /// If the contract instance ledger entry should be included in the output
+    #[arg(long = "instance", required_unless_present_any = vec!("key", "key_xdr"))]
+    pub instance: bool,
 }
 
 #[derive(thiserror::Error, Debug)]
@@ -57,6 +61,15 @@ impl Cmd {
             .contract
             .resolve_contract_id(&self.args.locator, &network.network_passphrase)?;
         let contract_address_arg = ScAddress::Contract(ContractId(Hash(contract_id.0)));
+        if self.instance {
+            let contract_instance_key = LedgerKey::ContractData(LedgerKeyContractData {
+                contract: contract_address_arg.clone(),
+                key: ScVal::LedgerKeyContractInstance,
+                durability: ContractDataDurability::Persistent,
+            });
+
+            ledger_keys.push(contract_instance_key);
+        }
 
         if let Some(keys) = &self.key {
             for key in keys {