fix: sign restore and last-trade-index requests with identity keys

Restore and LastTradeIndex are account-scoped queries: Mostro looks up
the user by the sender pubkey on the gift wrap, so signing with a
per-trade key leaves the request either resolving to an unknown user
or to stale trade-index state — either way, recovery flows silently
return nothing.

Revert these two call sites to `identity_keys` as the signer, and
route `wait_for_dm` / `parse_dm_events` on the same key so the
response (which Mostro addresses back to the sender pubkey) is the
one we subscribe to and can decrypt.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: grunch

src/cli/last_trade_index.rs

@@ -23,10 +23,13 @@ pub async fn execute_last_trade_index(
         .as_json()
         .map_err(|_| anyhow::anyhow!("Failed to serialize message"))?;
 
-    // Send the last trade index message to Mostro server
+    // LastTradeIndex is account-scoped: the answer depends on which user
+    // is asking, and Mostro looks that up by the sender pubkey. Sign with
+    // `identity_keys` so the request resolves to the account, not to a
+    // (possibly unregistered) trade key.
     let sent_message = send_dm(
         &ctx.client,
-        &ctx.trade_keys,
+        identity_keys,
         &mostro_key,
         message_json,
         None,
@@ -41,10 +44,10 @@ pub async fn execute_last_trade_index(
     println!();
 
     // Wait for incoming DM
-    let recv_event = wait_for_dm(ctx, Some(&ctx.trade_keys), sent_message).await?;
+    let recv_event = wait_for_dm(ctx, Some(identity_keys), sent_message).await?;
 
     // Parse the incoming DM
-    let messages = parse_dm_events(recv_event, &ctx.trade_keys, None).await;
+    let messages = parse_dm_events(recv_event, identity_keys, None).await;
     if let Some((message, _, _)) = messages.first() {
         let message = message.get_inner_message_kind();
         if message.action == Action::LastTradeIndex {

src/cli/restore.rs

@@ -19,10 +19,13 @@ pub async fn execute_restore(
         .as_json()
         .map_err(|_| anyhow::anyhow!("Failed to serialize message"))?;
 
-    // Send the restore message to Mostro server
+    // Restore is account-scoped: Mostro indexes users by their identity
+    // pubkey, so the whole exchange (send, wait, decrypt) runs on
+    // `identity_keys` — an unregistered trade key would look like an
+    // unknown user and recovery would silently return nothing.
     let sent_message = send_dm(
         &ctx.client,
-        &ctx.trade_keys,
+        identity_keys,
         &mostro_key,
         message_json,
         None,
@@ -48,10 +51,10 @@ pub async fn execute_restore(
     println!("⏳ Recovering pending orders and disputes...\n");
 
     // Wait for incoming DM
-    let recv_event = wait_for_dm(ctx, Some(&ctx.trade_keys), sent_message).await?;
+    let recv_event = wait_for_dm(ctx, Some(identity_keys), sent_message).await?;
 
     // Parse the incoming DM
-    let messages = parse_dm_events(recv_event, &ctx.trade_keys, None).await;
+    let messages = parse_dm_events(recv_event, identity_keys, None).await;
     if let Some((message, _, _)) = messages.first() {
         let message = message.get_inner_message_kind();
         if message.action == Action::RestoreSession {