Add ability to expand and collapse long quoted messages (#6701)

In case where we had a very long message the experience of going between 
messages to see the full quote isn't very nice on desktop, therefore this commit
adds a button with additional hotkey to normalize the experience a bit.

Fixes https://github.com/vector-im/element-web/issues/18884

res/img/element-icons/collapse-message.svg

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res/img/element-icons/expand-message.svg

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+<svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 11 14"><defs/><path fill="#17191C" fill-rule="evenodd" d="M.2192 8.494a.753.753 0 011.0623-.0018l3.7243 3.7003 3.7123-3.7123a.753.753 0 011.0624-.0017.747.747 0 01.0017 1.059L5.5396 13.78a.753.753 0 01-1.0624.0018L.221 9.5528A.747.747 0 01.2192 8.494zM9.7822 5.5063A.753.753 0 018.72 5.508L4.9956 1.8077 1.2833 5.52a.753.753 0 01-1.0624.0018.747.747 0 01-.0017-1.059L4.4618.2202A.753.753 0 015.5242.2185l4.2563 4.2289a.747.747 0 01.0017 1.0589z" clip-rule="evenodd"/></svg>