Make some strings in WebUI translatable

Closes #14920

src/webui/www/private/views/preferences.html

@@ -230,7 +230,7 @@
         <div class="formRow">
             <label for="port_value">QBT_TR(Port used for incoming connections:)QBT_TR[CONTEXT=OptionsDialog]</label>
             <input type="text" id="port_value" style="width: 4em;" />
-            <button style="margin-left: 1em;" onclick="qBittorrent.Preferences.generateRandomPort();">Random</button>
+            <button style="margin-left: 1em;" onclick="qBittorrent.Preferences.generateRandomPort();">QBT_TR(Random)QBT_TR[CONTEXT=OptionsDialog]</button>
         </div>
         <div class="formRow">
             <input type="checkbox" id="upnp_checkbox" />

src/webui/www/private/views/rss.html

@@ -599,7 +599,7 @@
                         // Unread entry at top
                         rssFeedTable.updateRowData({
                             rowId: 0,
-                            name: 'Unread',
+                            name: 'QBT_TR(Unread)QBT_TR[CONTEXT=FeedListWidget]',
                             unread: 0,
                             status: 'unread',
                             indentation: 0,

src/webui/www/private/views/search.html

@@ -117,7 +117,7 @@
             <div id="searchResultsGranularFilters">
                 <span style="margin-left: 15px;">QBT_TR(Seeds:)QBT_TR[CONTEXT=SearchEngineWidget]</span>
                 <input type="number" min="0" max="1000" id="searchMinSeedsFilter" value="0" onchange="qBittorrent.Search.searchSeedsFilterChanged()">
-                <span>to</span>
+                <span>QBT_TR(to)QBT_TR[CONTEXT=SearchEngineWidget]</span>
                 <input type="number" min="0" max="1000" id="searchMaxSeedsFilter" value="0" onchange="qBittorrent.Search.searchSeedsFilterChanged()">
 
                 <span style="margin-left: 15px;">QBT_TR(Size:)QBT_TR[CONTEXT=SearchEngineWidget]</span>
@@ -131,7 +131,7 @@
                     <option value="5">QBT_TR(PiB)QBT_TR[CONTEXT=misc]</option>
                     <option value="6">QBT_TR(EiB)QBT_TR[CONTEXT=misc]</option>
                 </select>
-                <span>to</span>
+                <span>QBT_TR(to)QBT_TR[CONTEXT=SearchEngineWidget]</span>
                 <input type="number" min="0" max="1000" step=".01" value="0.00" id="searchMaxSizeFilter" onchange="qBittorrent.Search.searchSizeFilterChanged()">
                 <select id="searchMaxSizePrefix" onchange="qBittorrent.Search.searchSizeFilterPrefixChanged()">
                     <option value="0">QBT_TR(B)QBT_TR[CONTEXT=misc]</option>