fix(backend,domain,infrastructure,frontend): réconcilie les états et tâches fantômes au démarrage — #307 (cause: l'activation projet balayait tous les documents background-task sous le root sans filtre project_id et LiveState::reconcile_orphans conservait correlation_id des lignes mortes, laissant après reboot des LED working fantômes et des tâches Running orphelines reprojetées par GetProjectWorkState, tandis qu'un conversationId isolé affichait indéfiniment « Conversation liée — récupération du transcript en cours. »; fix backend: FsBackgroundTaskStore::reconcile_project_boot borne la réconciliation boot au document du projet activé (API reconcile_boot historique préservée), AppBackgroundTaskStore filtre list_undelivered_completions sur project_id, et une ligne active orpheline efface désormais aussi correlation_id en plus de ticket/last_delegation; garde-fou frontend: CustomAgentChatView affiche l'état terminal « Conversation liée — transcript indisponible. » quand openOrAttach terminé n'a récupéré aucun tour, spinner borné à opening, conversationId et cellule préservés; QA verte reconfirmée par Git: rustup run stable cargo fmt --all -- --check, git diff --check, cargo test -p infrastructure --test background_task_store 12/12 dont project_reconcile_does_not_repair_or_report_foreign_project_tasks, -p domain --lib live_state 15/15, -p backend ticket307_activation_reconcile_tests 1/1 (activate_project_clears_stale_live_correlation_and_terminalizes_orphan_task) et background_tasks_b7 1/1 renforcé (orphan évicté de list_open_for_agent), -p application --test workstate 29/29, cargo check -p backend, frontend npm test CustomAgentChatView 72/72 dont garde-fou transcript indisponible, npm run typecheck; risque résiduel documenté: le garde-fou suppose que openOrAttach finit par se résoudre, pas de timeout transport ajouté; fichiers .ideai/tickets/296/*, tickets/299-307/*, counter/index, attachments/ et scripts/ hors périmètre et préservés en worktree; aucun push)

crates/infrastructure/src/store/background_task.rs

@@ -120,6 +120,31 @@ impl FsBackgroundTaskStore {
         &self,
         live_task_ids: &[TaskId],
         now_ms: u64,
+    ) -> Result<BackgroundTaskReconcileReport, BackgroundTaskPortError> {
+        self.reconcile_boot_inner(None, live_task_ids, now_ms).await
+    }
+
+    /// Reconciles only the document owned by `project_id`.
+    ///
+    /// The filesystem adapter is normally rooted at one project, but documents
+    /// remain keyed by project id. Activation must therefore stay explicitly
+    /// project-scoped and must not repair or report a foreign/stale document that
+    /// happens to exist below the same root.
+    pub async fn reconcile_project_boot(
+        &self,
+        project_id: ProjectId,
+        live_task_ids: &[TaskId],
+        now_ms: u64,
+    ) -> Result<BackgroundTaskReconcileReport, BackgroundTaskPortError> {
+        self.reconcile_boot_inner(Some(project_id), live_task_ids, now_ms)
+            .await
+    }
+
+    async fn reconcile_boot_inner(
+        &self,
+        only_project_id: Option<ProjectId>,
+        live_task_ids: &[TaskId],
+        now_ms: u64,
     ) -> Result<BackgroundTaskReconcileReport, BackgroundTaskPortError> {
         let live: HashSet<TaskId> = live_task_ids.iter().copied().collect();
         let mut state = self.read_all_docs().await?;
@@ -127,6 +152,9 @@ impl FsBackgroundTaskStore {
         let mut changed_projects = BTreeSet::new();
 
         for (project_id, doc) in &mut state.docs {
+            if only_project_id.is_some_and(|expected| expected != *project_id) {
+                continue;
+            }
             for task in &mut doc.tasks {
                 match task.state {
                     BackgroundTaskState::Running

crates/infrastructure/tests/background_task_store.rs

@@ -381,6 +381,34 @@ async fn reconcile_marks_running_without_live_handle_failed_and_pending() {
     );
 }
 
+#[tokio::test]
+async fn project_reconcile_does_not_repair_or_report_foreign_project_tasks() {
+    let tmp = TempDir::new();
+    let store = FsBackgroundTaskStore::new(&tmp.project_path());
+    let owned = running_task(1, 10, 100, 1_000);
+    let foreign = running_task(2, 20, 100, 1_000);
+
+    store.create(&owned).await.unwrap();
+    store.create(&foreign).await.unwrap();
+
+    let report = store
+        .reconcile_project_boot(owned.project_id, &[], 2_000)
+        .await
+        .unwrap();
+
+    assert_eq!(report.failed_task_ids, vec![owned.id]);
+    assert_eq!(report.delivery_pending_task_ids, vec![owned.id]);
+    assert_eq!(
+        store.get(owned.id).await.unwrap().unwrap().state,
+        BackgroundTaskState::Failed
+    );
+    assert_eq!(
+        store.get(foreign.id).await.unwrap().unwrap().state,
+        BackgroundTaskState::Running,
+        "activating one project must not mutate another project's persisted task"
+    );
+}
+
 #[tokio::test]
 async fn reconcile_marks_cancelling_without_live_handle_cancel_failed_and_pending() {
     let tmp = TempDir::new();