refactor: Phase E — types de réponses API standardisés + SVGs inline → Icon

E1 - API responses:
- Crée responses.rs avec OkResponse, DeletedResponse, UpdatedResponse,
  RevokedResponse, UnlinkedResponse, StatusResponse (6 tests de sérialisation)
- Remplace ~15 json!() inline par des types structurés dans books, libraries,
  tokens, users, handlers, anilist, metadata, download_detection, torrent_import
- Signatures de retour des handlers typées (plus de serde_json::Value)

E2 - SVGs → Icon component:
- Ajoute icon "lock" au composant Icon
- Remplace ~30 SVGs inline par <Icon> dans 9 composants
  (FolderPicker, FolderBrowser, LiveSearchForm, JobRow, LibraryActions,
  ReadingStatusModal, EditBookForm, EditSeriesForm, UserSwitcher)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/api/src/responses.rs

@@ -0,0 +1,133 @@
+use serde::Serialize;
+use utoipa::ToSchema;
+use uuid::Uuid;
+
+/// Simple acknowledgment response.
+#[derive(Debug, Serialize, ToSchema)]
+pub struct OkResponse {
+    pub ok: bool,
+}
+
+impl OkResponse {
+    pub fn new() -> Self {
+        Self { ok: true }
+    }
+}
+
+/// Response for resource deletion operations.
+#[derive(Debug, Serialize, ToSchema)]
+pub struct DeletedResponse {
+    pub deleted: bool,
+    pub id: Uuid,
+}
+
+impl DeletedResponse {
+    pub fn new(id: Uuid) -> Self {
+        Self { deleted: true, id }
+    }
+}
+
+/// Response for resource update operations.
+#[derive(Debug, Serialize, ToSchema)]
+pub struct UpdatedResponse {
+    pub updated: bool,
+    pub id: Uuid,
+}
+
+impl UpdatedResponse {
+    pub fn new(id: Uuid) -> Self {
+        Self { updated: true, id }
+    }
+}
+
+/// Response for token revocation.
+#[derive(Debug, Serialize, ToSchema)]
+pub struct RevokedResponse {
+    pub revoked: bool,
+    pub id: Uuid,
+}
+
+impl RevokedResponse {
+    pub fn new(id: Uuid) -> Self {
+        Self { revoked: true, id }
+    }
+}
+
+/// Response for unlinking operations (e.g., AniList).
+#[derive(Debug, Serialize, ToSchema)]
+pub struct UnlinkedResponse {
+    pub unlinked: bool,
+}
+
+impl UnlinkedResponse {
+    pub fn new() -> Self {
+        Self { unlinked: true }
+    }
+}
+
+/// Simple status response.
+#[derive(Debug, Serialize, ToSchema)]
+pub struct StatusResponse {
+    pub status: String,
+}
+
+impl StatusResponse {
+    pub fn new(status: &str) -> Self {
+        Self {
+            status: status.to_string(),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn ok_response_serializes() {
+        let r = OkResponse::new();
+        let json = serde_json::to_value(&r).unwrap();
+        assert_eq!(json, serde_json::json!({"ok": true}));
+    }
+
+    #[test]
+    fn deleted_response_serializes() {
+        let id = Uuid::nil();
+        let r = DeletedResponse::new(id);
+        let json = serde_json::to_value(&r).unwrap();
+        assert_eq!(json["deleted"], true);
+        assert_eq!(json["id"], id.to_string());
+    }
+
+    #[test]
+    fn updated_response_serializes() {
+        let id = Uuid::nil();
+        let r = UpdatedResponse::new(id);
+        let json = serde_json::to_value(&r).unwrap();
+        assert_eq!(json["updated"], true);
+        assert_eq!(json["id"], id.to_string());
+    }
+
+    #[test]
+    fn revoked_response_serializes() {
+        let id = Uuid::nil();
+        let r = RevokedResponse::new(id);
+        let json = serde_json::to_value(&r).unwrap();
+        assert_eq!(json["revoked"], true);
+        assert_eq!(json["id"], id.to_string());
+    }
+
+    #[test]
+    fn unlinked_response_serializes() {
+        let r = UnlinkedResponse::new();
+        let json = serde_json::to_value(&r).unwrap();
+        assert_eq!(json, serde_json::json!({"unlinked": true}));
+    }
+
+    #[test]
+    fn status_response_serializes() {
+        let r = StatusResponse::new("ready");
+        let json = serde_json::to_value(&r).unwrap();
+        assert_eq!(json, serde_json::json!({"status": "ready"}));
+    }
+}