feat(bulk-report-replies): add feature with non-functional UI

This commit adds a new "bulk report replies" feature along with its UI.
The underlying logic will be implemented soon.

Bug: twpowertools:192
Change-Id: I6a6a636c7186485154c32dbbec001493b3b0458f
diff --git a/src/static/_locales/en/messages.json b/src/static/_locales/en/messages.json
index 4c655f7..d4f2571 100644
--- a/src/static/_locales/en/messages.json
+++ b/src/static/_locales/en/messages.json
@@ -183,6 +183,10 @@
     "message": "Tentative fix for CC slowness and high memory usage (<a href='https://s.iavm.xyz/cc-running-slow-pekb'><code>pekb/269560789</code></a>).",
     "description": "Feature checkbox in the options page"
   },
+  "options_bulkreportreplies": {
+    "message": "Enable the ability to bulk report replies.",
+    "description": "Feature checkbox in the options page"
+  },
   "options_save": {
     "message": "Save",
     "description": "Button in the options page to save the settings"
diff --git a/src/static/css/common/console.css b/src/static/css/common/console.css
index 68724b4..805e1e2 100644
--- a/src/static/css/common/console.css
+++ b/src/static/css/common/console.css
@@ -169,7 +169,7 @@
  * that case, only users who have enabled one of the specified features will
  * experience the breakage.
  **/
-body.TWPT-flattenthreads-enabled {
+body:is(.TWPT-flattenthreads-enabled, .TWPT-bulkreportreplies-enabled) {
   ec-thread sc-tailwind-thread-message-message-list sc-tailwind-thread-message-message-actions {
     display: flex;
     flex-direction: row;
diff --git a/src/static/options/experiments.html b/src/static/options/experiments.html
index 9a21fdf..7eed0fb 100644
--- a/src/static/options/experiments.html
+++ b/src/static/options/experiments.html
@@ -15,6 +15,7 @@
         <div id="optional-permissions-warning" hidden data-i18n="optionalpermissionswarning_header"></div>
         <div class="option"><input type="checkbox" id="workflows"> <label for="workflows" data-i18n="workflows"></label> <button id="manage-workflows" data-i18n="workflows_manage"></button></div>
         <div class="option"><input type="checkbox" id="extrainfo"> <label for="extrainfo" data-i18n="extrainfo"></label></div>
+        <div class="option"><input type="checkbox" id="bulkreportreplies"> <label for="bulkreportreplies" data-i18n="bulkreportreplies"></label></div>
         <div class="actions"><button id="save" data-i18n="save"></button></div>
       </form>
       <div id="save-indicator"></div>