fix: carry tool input in ApprovalRequired event so approval dialog always shows params

The ApprovalRequest params_display() relied on pending_tool_uses,
which gets drained by MessageComplete before ApprovalRequired arrives
in the TUI event loop. When the model streaming response contained a
text block, ContentBlockStop(Text) set pending_message_complete=true,
triggering the drain and leaving the approval dialog with empty {}.

Fix: add input: Value to Event::ApprovalRequired and populate it
from tool_input in the engine tool execution loop. The TUI now reads
params directly from the event instead of searching pending_tool_uses.

crates/tui/src/core/engine/turn_loop.rs

@@ -1696,6 +1696,7 @@ impl Engine {
                                 .send(Event::ApprovalRequired {
                                     id: tool_id.clone(),
                                     tool_name: tool_name.clone(),
+                                    input: tool_input.clone(),
                                     description: plan.approval_description.clone(),
                                     approval_key,
                                     approval_grouping_key,

crates/tui/src/core/events.rs

@@ -226,6 +226,9 @@ pub enum Event {
         id: String,
         tool_name: String,
         description: String,
+        /// Tool parameters for approval display. Carried on the event so the
+        /// TUI does not need to reconstruct them from `pending_tool_uses`.
+        input: Value,
         /// Exact-argument fingerprint, used to scope *denials* (#1617).
         approval_key: String,
         /// Lossy / arity-aware fingerprint, used to scope *approvals* so an

crates/tui/src/runtime_threads.rs

@@ -4172,6 +4172,7 @@ mod tests {
                 id: "tool_stale".to_string(),
                 tool_name: "exec_command".to_string(),
                 description: "stale approval".to_string(),
+                input: serde_json::json!({}),
             })
             .await?;
 
@@ -4245,6 +4246,7 @@ mod tests {
                 id: "tool_external_allow".to_string(),
                 tool_name: "exec_command".to_string(),
                 description: "external allow".to_string(),
+                input: serde_json::json!({}),
             })
             .await?;
 
@@ -4322,6 +4324,7 @@ mod tests {
                 id: "tool_external_deny".to_string(),
                 tool_name: "exec_command".to_string(),
                 description: "external deny".to_string(),
+                input: serde_json::json!({}),
             })
             .await?;
 
@@ -4508,6 +4511,7 @@ mod tests {
                 id: "tool_remember".to_string(),
                 tool_name: "exec_command".to_string(),
                 description: "remember=true".to_string(),
+                input: serde_json::json!({}),
             })
             .await?;
 

crates/tui/src/tui/ui.rs

@@ -1893,6 +1893,7 @@ async fn run_event_loop(
                         id,
                         tool_name,
                         description,
+                        input,
                         approval_key,
                         approval_grouping_key,
                     } => {
@@ -1937,12 +1938,7 @@ async fn run_event_loop(
                             app.status_message =
                                 Some(format!("Blocked tool '{tool_name}' (approval_mode=never)"));
                         } else {
-                            let tool_input = app
-                                .pending_tool_uses
-                                .iter()
-                                .find(|(tool_id, _, _)| tool_id == &id)
-                                .map(|(_, _, input)| input.clone())
-                                .unwrap_or_else(|| serde_json::json!({}));
+                            let tool_input = input;
 
                             if tool_name == "apply_patch" {
                                 maybe_add_patch_preview(app, &tool_input);