Preserve QPowerPoint slide transitions in PPTX

src/features/qpowerpoint/QPowerPoint.tsx

@@ -1,7 +1,7 @@
 import { useRef, useState } from "react";
 import type { CSSProperties } from "react";
-import { Copy, Download, EyeOff, FileText, FileUp, Image as ImageIcon, Palette, Plus, Save, Trash2 } from "lucide-react";
-import type { Slide, SlideDeck, SlideImage } from "../../types";
+import { Copy, Download, EyeOff, FileText, FileUp, Image as ImageIcon, Palette, Play, Plus, Save, Trash2 } from "lucide-react";
+import type { Slide, SlideDeck, SlideImage, SlideTransition } from "../../types";
 import { downloadBlobFile, downloadTextFile } from "../../utils/download";
 import { exportPptxBlob, importPptxFile } from "../../io/powerPointOffice";
 import { replaceFileExtension } from "../../io/fileHelpers";
@@ -40,6 +40,12 @@ const textColorSwatches = [
 const slideFontFamilyOptions = ["Aptos", "Calibri", "Courier New", "Times New Roman"];
 const titleFontSizeOptions = [24, 28, 30, 34, 40, 44, 48];
 const subtitleFontSizeOptions = [14, 16, 18, 20, 22, 24, 28];
+const slideTransitionOptions: Array<{ value: SlideTransition | ""; label: string }> = [
+  { value: "", label: "Без перехода" },
+  { value: "fade", label: "Растворение" },
+  { value: "push", label: "Сдвиг" },
+  { value: "wipe", label: "Шторка" }
+];
 
 const slideWidthInches = 13.333;
 const slideHeightInches = 7.5;
@@ -448,6 +454,25 @@ export function QPowerPoint({ deck, onChange }: QPowerPointProps) {
               ))}
             </select>
           </label>
+          <label>
+            <span>
+              <Play size={16} />
+              Переход
+            </span>
+            <select
+              value={activeSlide.transition ?? ""}
+              onChange={(event) => {
+                const transition = event.target.value as SlideTransition | "";
+                updateSlide({ ...activeSlide, transition: transition || undefined });
+              }}
+            >
+              {slideTransitionOptions.map((option) => (
+                <option key={option.value || "none"} value={option.value}>
+                  {option.label}
+                </option>
+              ))}
+            </select>
+          </label>
           <div className="slide-background-swatches" aria-label="Фон слайда">
             {backgroundColorSwatches.map((swatch) => (
               <button