feat(tickets): suppression d'un ticket (backend + frontend)

Ajoute la suppression complète d'un ticket (#6).

Backend Rust :
- port IssueStore::delete (NotFound si absent) + event IssueDeleted{freed_sprint}
- FsIssueStore::delete : supprime .ideai/tickets/<N>/ et l'index sous lock
- use case DeleteIssue + adaptations des tests sprint/ticket_assistant au port
- commande Tauri ticket_delete + câblage events/state/lib

Frontend :
- gateway delete (ports, adapter ticket + mock, domain)
- useTicketDetail : retrait de la liste et fermeture du détail via event issueDeleted
- intégration TicketDetail + tests

Tests verts : application/issue_usecases (6), infrastructure/issue_store (7),
app-tauri --lib (56), frontend vitest (503), npm run build (exit 0).

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

crates/application/src/issues/mod.rs

@@ -161,6 +161,59 @@ impl ReadIssue {
     }
 }
 
+/// Input for [`DeleteIssue::execute`].
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DeleteIssueInput {
+    /// Project owning the issue.
+    pub project: Project,
+    /// Issue reference.
+    pub issue_ref: IssueRef,
+}
+
+/// Output of [`DeleteIssue::execute`].
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DeleteIssueOutput {
+    /// Deleted issue reference.
+    pub issue_ref: IssueRef,
+}
+
+/// Deletes an issue.
+pub struct DeleteIssue {
+    issues: Arc<dyn IssueStore>,
+    events: Arc<dyn EventBus>,
+}
+
+impl DeleteIssue {
+    /// Builds the use case.
+    #[must_use]
+    pub fn new(issues: Arc<dyn IssueStore>, events: Arc<dyn EventBus>) -> Self {
+        Self { issues, events }
+    }
+
+    /// Executes deletion.
+    ///
+    /// # Errors
+    /// [`AppError`] on missing issue or store failure.
+    pub async fn execute(&self, input: DeleteIssueInput) -> Result<DeleteIssueOutput, AppError> {
+        let issue = self
+            .issues
+            .get_by_ref(&input.project.root, input.issue_ref)
+            .await?;
+        let freed_sprint = issue.sprint;
+        self.issues
+            .delete(&input.project.root, input.issue_ref)
+            .await?;
+        self.events.publish(DomainEvent::IssueDeleted {
+            project_id: input.project.id,
+            issue_ref: input.issue_ref,
+            freed_sprint,
+        });
+        Ok(DeleteIssueOutput {
+            issue_ref: input.issue_ref,
+        })
+    }
+}
+
 /// Input for [`ReadIssueCarnet::execute`].
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ReadIssueCarnetInput {

crates/application/src/lib.rs

@@ -79,11 +79,11 @@ pub use git::{
 pub use health::{HealthInput, HealthReport, HealthUseCase};
 pub use issues::{
     AssignIssueAgent, AssignIssueAgentInput, AssignIssueAgentOutput, CreateIssue, CreateIssueInput,
-    CreateIssueOutput, LinkIssues, LinkIssuesInput, LinkIssuesOutput, ListIssues, ListIssuesInput,
-    ListIssuesOutput, ReadIssue, ReadIssueCarnet, ReadIssueCarnetInput, ReadIssueCarnetOutput,
-    ReadIssueInput, ReadIssueOutput, UnlinkIssues, UnlinkIssuesInput, UpdateIssue,
-    UpdateIssueCarnet, UpdateIssueCarnetInput, UpdateIssueCarnetOutput, UpdateIssueInput,
-    UpdateIssueOutput,
+    CreateIssueOutput, DeleteIssue, DeleteIssueInput, DeleteIssueOutput, LinkIssues,
+    LinkIssuesInput, LinkIssuesOutput, ListIssues, ListIssuesInput, ListIssuesOutput, ReadIssue,
+    ReadIssueCarnet, ReadIssueCarnetInput, ReadIssueCarnetOutput, ReadIssueInput, ReadIssueOutput,
+    UnlinkIssues, UnlinkIssuesInput, UpdateIssue, UpdateIssueCarnet, UpdateIssueCarnetInput,
+    UpdateIssueCarnetOutput, UpdateIssueInput, UpdateIssueOutput,
 };
 pub use layout::{
     CreateLayout, CreateLayoutInput, CreateLayoutOutput, DeleteLayout, DeleteLayoutInput,