feat(bookstack-api-9xo): implement BooksService List and Get

Add listResponse generic type and ListOptions.queryString() helper.
Implement BooksService.List with pagination support and Get with
proper error handling. Include mock server tests.

books_test.go

@@ -0,0 +1,102 @@
+package bookstack
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"testing"
+)
+
+func TestBooksService_List(t *testing.T) {
+	c := testClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "GET" {
+			t.Errorf("method = %s, want GET", r.Method)
+		}
+		if r.URL.Path != "/api/books" {
+			t.Errorf("path = %s, want /api/books", r.URL.Path)
+		}
+		json.NewEncoder(w).Encode(map[string]any{
+			"data": []map[string]any{
+				{"id": 1, "name": "Book One", "slug": "book-one"},
+				{"id": 2, "name": "Book Two", "slug": "book-two"},
+			},
+			"total": 2,
+		})
+	})
+
+	books, err := c.Books.List(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(books) != 2 {
+		t.Fatalf("got %d books, want 2", len(books))
+	}
+	if books[0].Name != "Book One" {
+		t.Errorf("books[0].Name = %q, want %q", books[0].Name, "Book One")
+	}
+}
+
+func TestBooksService_List_WithOptions(t *testing.T) {
+	c := testClient(t, func(w http.ResponseWriter, r *http.Request) {
+		q := r.URL.Query()
+		if q.Get("count") != "10" {
+			t.Errorf("count = %q, want 10", q.Get("count"))
+		}
+		if q.Get("offset") != "20" {
+			t.Errorf("offset = %q, want 20", q.Get("offset"))
+		}
+		if q.Get("sort") != "-name" {
+			t.Errorf("sort = %q, want -name", q.Get("sort"))
+		}
+		json.NewEncoder(w).Encode(map[string]any{"data": []any{}, "total": 0})
+	})
+
+	_, err := c.Books.List(context.Background(), &ListOptions{
+		Count:  10,
+		Offset: 20,
+		Sort:   "-name",
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}
+
+func TestBooksService_Get(t *testing.T) {
+	c := testClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/api/books/42" {
+			t.Errorf("path = %s, want /api/books/42", r.URL.Path)
+		}
+		json.NewEncoder(w).Encode(map[string]any{
+			"id": 42, "name": "My Book", "slug": "my-book",
+		})
+	})
+
+	book, err := c.Books.Get(context.Background(), 42)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if book.ID != 42 {
+		t.Errorf("ID = %d, want 42", book.ID)
+	}
+	if book.Name != "My Book" {
+		t.Errorf("Name = %q, want %q", book.Name, "My Book")
+	}
+}
+
+func TestBooksService_Get_NotFound(t *testing.T) {
+	c := testClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		json.NewEncoder(w).Encode(map[string]any{
+			"error": map[string]string{"message": "Book not found"},
+		})
+	})
+
+	_, err := c.Books.Get(context.Background(), 999)
+	if err == nil {
+		t.Fatal("expected error")
+	}
+	if !errors.Is(err, ErrNotFound) {
+		t.Error("expected ErrNotFound")
+	}
+}