feat(tickets): filtres multi-critères par cases à cocher (backend + frontend)

Passe les filtres de la liste des tickets en sélection multiple (#12).

Backend Rust :
- IssueListFilter : statuses/priorities en Vec, filter_matches en OR intra-champ
  et AND inter-champs
- TicketListRequestDto en tableaux + from_request (parse/déduplication)
- MCP idea_ticket_list aligné sur le nouveau contrat

Frontend :
- TicketListQuery.statuses/priorities
- UI de cases à cocher, toggle/clear des filtres

Tests verts : issue_store (7), app-tauri --lib (59), mcp_server (24),
issue_usecases (6), sprint_usecases (6), frontend vitest (505), npm run build (exit 0).

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

crates/domain/src/issue.rs

@@ -426,10 +426,10 @@ impl From<&Issue> for IssueIndexEntry {
 /// Store-side list filter.
 #[derive(Debug, Clone, Default, PartialEq, Eq)]
 pub struct IssueListFilter {
-    /// Optional status filter.
-    pub status: Option<IssueStatus>,
-    /// Optional priority filter.
-    pub priority: Option<IssuePriority>,
+    /// Allowed statuses. Empty means every status.
+    pub statuses: Vec<IssueStatus>,
+    /// Allowed priorities. Empty means every priority.
+    pub priorities: Vec<IssuePriority>,
     /// Optional assigned agent filter.
     pub assigned_agent_id: Option<AgentId>,
     /// Optional sprint membership filter.