feat(inter-agent): backend des annonces live d'agent (B0-B3)

Redémarre le ticket #4 sur la base develop. Émission d'annonces live d'un
agent vers l'UI, distinctes du Final de délégation :

- domain: ReplyEvent::Announcement/Final et DomainEvent::AgentAnnouncement
  (events.rs), port d'émission (ports.rs), gating de readiness (readiness.rs).
- application: mapping des événements structurés en annonces
  (agent/structured.rs, agent/mod.rs, lib.rs) et relais côté orchestrateur
  (orchestrator/service.rs).
- infrastructure/session: parse des annonces + fix du Final pour Claude et
  Codex, propagé aux adaptateurs et à la conformance
  (claude.rs, codex.rs, conformance.rs, mod.rs, process.rs, sandbox_e2e.rs).
- app-tauri: relais Tauri des annonces vers le front (events.rs, chat.rs).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

crates/infrastructure/src/session/sandbox_e2e.rs

@@ -139,7 +139,7 @@ async fn pty_structured_run_turn_enforces_plan_end_to_end() {
     );
     let enforcer = crate::sandbox::default_enforcer();
 
-    let lines = run_turn(&spec, None, Some(&enforcer))
+    let lines = run_turn(&spec, None, Some(&enforcer), None)
         .await
         .expect("run_turn sandboxé réussit sous posture Ask");
 
@@ -182,7 +182,7 @@ async fn structured_run_turn_without_plan_does_not_sandbox() {
     let spec = writing_spawn_line(RESULT_LINE, &denied_marker, &allowed_marker, None);
     let enforcer = crate::sandbox::default_enforcer();
 
-    let lines = run_turn(&spec, None, Some(&enforcer))
+    let lines = run_turn(&spec, None, Some(&enforcer), None)
         .await
         .expect("run_turn natif réussit");
 
@@ -253,7 +253,7 @@ async fn structured_run_turn_fail_closed_no_child_on_enforce_err() {
     };
     let enforcer: Arc<dyn SandboxEnforcer> = Arc::new(AlwaysFailEnforcer);
 
-    let err = run_turn(&spec, None, Some(&enforcer))
+    let err = run_turn(&spec, None, Some(&enforcer), None)
         .await
         .expect_err("enforce Err ⇒ run_turn doit échouer (fail-closed)");
     assert!(
@@ -296,7 +296,7 @@ async fn structured_run_turn_none_plan_is_native_path() {
     let enforcer = crate::sandbox::default_enforcer();
 
     // Enforcer fourni MAIS plan None ⇒ la branche sandboxée n'est pas prise.
-    let lines = run_turn(&spec, None, Some(&enforcer))
+    let lines = run_turn(&spec, None, Some(&enforcer), None)
         .await
         .expect("chemin natif réussit");
     assert_eq!(lines, vec![RESULT_LINE.to_owned()]);
@@ -330,7 +330,7 @@ async fn structured_two_turns_disjoint_grants_are_confined() {
     let a_in = dir_a.join("in.txt");
     let a_into_b = dir_b.join("from-a.txt");
     let spec_a = writing_spawn_line(RESULT_LINE, &a_into_b, &a_in, Some(rw_plan(&dir_a)));
-    run_turn(&spec_a, None, Some(&enforcer))
+    run_turn(&spec_a, None, Some(&enforcer), None)
         .await
         .expect("tour A ok");
     assert!(
@@ -347,7 +347,7 @@ async fn structured_two_turns_disjoint_grants_are_confined() {
     let b_in = dir_b.join("in.txt");
     let b_into_a = dir_a.join("from-b.txt");
     let spec_b = writing_spawn_line(RESULT_LINE, &b_into_a, &b_in, Some(rw_plan(&dir_b)));
-    run_turn(&spec_b, None, Some(&enforcer))
+    run_turn(&spec_b, None, Some(&enforcer), None)
         .await
         .expect("tour B ok");
     assert!(
@@ -388,9 +388,14 @@ async fn structured_run_turn_timeout_under_sandbox() {
     let enforcer = crate::sandbox::default_enforcer();
 
     let started = Instant::now();
-    let err = run_turn(&spec, Some(Duration::from_millis(250)), Some(&enforcer))
-        .await
-        .expect_err("doit expirer");
+    let err = run_turn(
+        &spec,
+        Some(Duration::from_millis(250)),
+        Some(&enforcer),
+        None,
+    )
+    .await
+    .expect_err("doit expirer");
     let elapsed = started.elapsed();
 
     assert!(