Add most of the UI for the new room list's menu button

Incomplete implementation: buttons don't work, some text is missing, etc

res/img/feather-customised/archive.svg

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+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-archive"><polyline points="21 8 21 21 3 21 3 8"></polyline><rect x="1" y="3" width="22" height="5"></rect><line x1="10" y1="12" x2="14" y2="12"></line></svg>

res/img/feather-customised/more-horizontal.svg

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+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-more-horizontal"><circle cx="12" cy="12" r="1"></circle><circle cx="19" cy="12" r="1"></circle><circle cx="5" cy="12" r="1"></circle></svg>

res/img/feather-customised/sun.svg

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+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-sun"><circle cx="12" cy="12" r="5"></circle><line x1="12" y1="1" x2="12" y2="3"></line><line x1="12" y1="21" x2="12" y2="23"></line><line x1="4.22" y1="4.22" x2="5.64" y2="5.64"></line><line x1="18.36" y1="18.36" x2="19.78" y2="19.78"></line><line x1="1" y1="12" x2="3" y2="12"></line><line x1="21" y1="12" x2="23" y2="12"></line><line x1="4.22" y1="19.78" x2="5.64" y2="18.36"></line><line x1="18.36" y1="5.64" x2="19.78" y2="4.22"></line></svg>