Added sitemap.xml file (#199)

## Target
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Added sitemap.xml file
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## Checklist
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- [ ] Documentation updated
- [x] Tests cover new or modified code
- [ ] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] New dependencies added
- [ ] Includes breaking changes
- [ ] Version bumped

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src/Cropper.Blazor/Client/wwwroot/sitemap.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+  <url>
+    <loc>https://cropperblazor.github.io/</loc>
+    <lastmod>2023-08-02T21:02:02+03:00</lastmod>
+    <changefreq>daily</changefreq>
+    <priority>1.0</priority>
+  </url>
+  <url>
+    <loc>https://cropperblazor.github.io/demo</loc>
+    <lastmod>2023-08-02T21:02:02+03:00</lastmod>
+    <changefreq>daily</changefreq>
+    <priority>0.9</priority>
+  </url>
+  <url>
+    <loc>https://cropperblazor.github.io/api</loc>
+    <lastmod>2023-08-02T21:02:02+03:00</lastmod>
+    <changefreq>daily</changefreq>
+    <priority>0.8</priority>
+  </url>
+  <url>
+    <loc>https://cropperblazor.github.io/about</loc>
+    <lastmod>2023-08-02T21:02:02+03:00</lastmod>
+    <changefreq>daily</changefreq>
+    <priority>0.7</priority>
+  </url>
+</urlset>