fix(tui): /compact <instructions> reach the compaction request

The queued /compact command drained into Effect::Compact with only the
session id, so the instructions typed after the command never reached the
shell's compaction prompt (which already accepts userContext). The effect
carries the parsed instructions, trimmed so an edited queue row with
leading whitespace still counts.

Ported from upstream 1.0.22 (grok-build dispatch/queue.rs).

Claude-Session: https://claude.ai/code/session_01RUqV8HVGXcAETyYbZ2tPQ4

crates/codegen/kigi-tui/src/app/effects/mod.rs

@@ -1388,13 +1388,18 @@ pub(crate) fn execute(
                     }
                 });
         }
-        Effect::Compact { agent_id, session_id } => {
+        Effect::Compact {
+            agent_id,
+            session_id,
+            user_context,
+        } => {
             let tx = acp_tx.clone();
             tasks
                 .spawn(async move {
-                    let params = serde_json::json!(
-                        { "sessionId" : session_id.0.to_string(), }
-                    );
+                    let params = serde_json::json!({
+                        "sessionId": session_id.0.to_string(),
+                        "userContext": user_context,
+                    });
                     let req = acp::ExtRequest::new(
                         "kigi/compact_conversation",
                         serde_json::value::to_raw_value(&params)