支持图标跟随主题，改进详情页，加入更好的多线程下载

新的下载会重试一个线程上的错误，一个线程崩溃次数过多会转移到队列里等待重新安排，其他的暂时没写

resource/icons/daynight-dark.svg

@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   width="48mm"
+   height="48mm"
+   viewBox="0 0 48 48"
+   version="1.1"
+   id="svg5"
+   inkscape:version="1.1.1 (3bf5ae0d25, 2021-09-20)"
+   sodipodi:docname="night.svg"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <sodipodi:namedview
+     id="namedview7"
+     pagecolor="#505050"
+     bordercolor="#eeeeee"
+     borderopacity="1"
+     inkscape:pageshadow="0"
+     inkscape:pageopacity="0"
+     inkscape:pagecheckerboard="0"
+     inkscape:document-units="mm"
+     showgrid="false"
+     width="48mm"
+     inkscape:zoom="3.0296134"
+     inkscape:cx="89.94547"
+     inkscape:cy="101.16802"
+     inkscape:window-width="1852"
+     inkscape:window-height="1021"
+     inkscape:window-x="68"
+     inkscape:window-y="30"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="layer2"
+     showguides="true"
+     inkscape:guide-bbox="true">
+    <sodipodi:guide
+       position="24.364586,23.954072"
+       orientation="0,-1"
+       id="guide1317" />
+  </sodipodi:namedview>
+  <defs
+     id="defs2" />
+  <g
+     inkscape:label="图层 1"
+     inkscape:groupmode="layer"
+     id="layer1">
+    <path
+       id="path846"
+       style="fill:#ffffff;fill-rule:evenodd;stroke:#000000;stroke-width:0;stroke-linecap:round;stroke-linejoin:round;stroke-miterlimit:4;stroke-dasharray:none;stroke-dashoffset:12;stroke-opacity:0.48333;paint-order:markers stroke fill"
+       d="M 20.08627,5.4455699 A 19.456798,19.456798 0 0 0 5.1481639,24.360177 19.456798,19.456798 0 0 0 24.604857,43.81687 19.456798,19.456798 0 0 0 42.756719,31.347865 17.271181,17.271181 0 0 1 32.437969,34.778662 17.271181,17.271181 0 0 1 15.166674,17.507366 17.271181,17.271181 0 0 1 20.08627,5.4455699 Z" />
+  </g>
+  <g
+     inkscape:groupmode="layer"
+     id="layer2"
+     inkscape:label="图层 2" />
+</svg>