[Minor] Add background icon to drop area

interface/css/rspamd.css

@@ -401,6 +401,14 @@ table#symbolsTable input[type="number"] {
 
 .outline-dashed-primary { outline: 2px dashed var(--bs-primary); }
 
+#scanMsgSource:placeholder-shown {
+  background-image: url("../img/drop-area.svg");
+  background-repeat: no-repeat;
+  background-position: center;
+  opacity: 0.8;
+}
+#scanMsgSource:not(:placeholder-shown) { background-image: none;}
+
 .scorebar-spam {
     background-color: rgba(240 0 0 / 0.1) !important;
 }

interface/img/drop-area.svg

@@ -0,0 +1,70 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   width="128"
+   height="128"
+   viewBox="0 0 128 128"
+   style="color:currentColor"
+   class="h-full w-full"
+   version="1.1"
+   id="svg3"
+   xml:space="preserve"
+   sodipodi:docname="mail-drop-area-50-3.svg"
+   inkscape:version="1.3.2 (091e20e, 2023-11-25, custom)"
+   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="namedview1"
+     pagecolor="#ffffff"
+     bordercolor="#000000"
+     borderopacity="0.25"
+     inkscape:showpageshadow="2"
+     inkscape:pageopacity="0.0"
+     inkscape:pagecheckerboard="0"
+     inkscape:deskcolor="#d1d1d1"
+     showgrid="true"
+     inkscape:zoom="2.96875"
+     inkscape:cx="123.28421"
+     inkscape:cy="45.136842"
+     inkscape:window-width="1680"
+     inkscape:window-height="997"
+     inkscape:window-x="-8"
+     inkscape:window-y="-8"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="svg3"><inkscape:grid
+       id="grid1"
+       units="px"
+       originx="0"
+       originy="0"
+       spacingx="8"
+       spacingy="8"
+       empcolor="#0099e5"
+       empopacity="0.30196078"
+       color="#0099e5"
+       opacity="0.14901961"
+       empspacing="2"
+       dotted="false"
+       gridanglex="30"
+       gridanglez="30"
+       visible="true" /></sodipodi:namedview><defs
+     id="defs3" /><g
+     style="color:currentColor"
+     id="g3"
+     transform="matrix(0.51136365,0,0,0.47727274,-32.109097,-24.66667)"><path
+       fill="currentColor"
+       d="M 303.32445,185.77778 H 166.43556 a 9.7777779,9.7777779 0 0 0 -9.77778,9.77778 v 97.77777 a 9.7777779,9.7777779 0 0 0 9.77778,9.77778 h 136.88889 a 9.7777779,9.7777779 0 0 0 9.77777,-9.77778 v -97.77777 a 9.7777779,9.7777779 0 0 0 -9.77777,-9.77778 z m -7.52889,107.55555 H 174.55111 l 34.22222,-35.39555 -7.04,-6.79556 -35.29777,36.52 v -84.67555 l 60.76888,60.47555 a 9.7777779,9.7777779 0 0 0 13.78667,0 l 62.33334,-61.99111 v 85.55556 l -35.98223,-35.98222 -6.89333,6.89333 z M 172.84,195.55556 H 295.40445 L 234.09778,256.52 Z"
+       class="clr-i-outline clr-i-outline-path-1"
+       id="path1-6"
+       style="fill:#ff6300;fill-opacity:1;stroke-width:4.88889"
+       inkscape:label="path3" /></g><g
+     id="g2"
+     transform="matrix(0.5,0,0,0.5,-84,-84)"><path
+       style="fill:#999999;fill-opacity:1"
+       d="m 216,216 8,40 8,-8 24,24 16,-16 -24,-24 8,-8 z"
+       id="path26"
+       inkscape:label="path2" /></g><g
+     id="g1"><path
+       id="use19"
+       style="fill:#4ac6ff;fill-opacity:1;stroke-width:4"
+       d="m 112,0 h 8 v 8 h -8 z M 32,80 h 8 v 8 H 32 Z M 96,0 h 8 v 8 h -8 z m 16,48 h 8 v 8 h -8 z m 0,-16 h 8 v 8 h -8 z m 0,-16 h 8 v 8 h -8 z M 80,0 h 8 V 8 H 80 Z M 64,0 h 8 V 8 H 64 Z M 48,0 h 8 V 8 H 48 Z M 32,0 h 8 V 8 H 32 Z M 16,0 h 8 V 8 H 16 Z M 0,0 H 8 V 8 H 0 Z m 0,16 h 8 v 8 H 0 Z m 0,16 h 8 v 8 H 0 Z m 0,16 h 8 v 8 H 0 Z m 0,16 h 8 v 8 H 0 Z m 0,16 h 8 v 8 H 0 Z m 16,0 h 8 v 8 h -8 z"
+       inkscape:label="path1" /></g></svg>