Use vertical layout for multiple code expander buttons (#31122) (#31152)

Use vertical layout for multiple code expander buttons (#31122) (#31152)

Backport #31122 by @silverwind

Fixes: https://github.com/go-gitea/gitea/issues/31068
- Now it only does a single call to `GetExpandDirection` per line
instead of multiples.
- Exposed `data-expand-direction` to frontend so it can correctly size
the buttons (it's a pain to do in tables).

<img width="142" alt="Screenshot 2024-05-27 at 20 44 56"
src="https://github.com/go-gitea/gitea/assets/115237/8b0b45a6-8e50-4081-8822-5e0775d8d941">
<img width="142" alt="Screenshot 2024-05-27 at 20 44 51"
src="https://github.com/go-gitea/gitea/assets/115237/b7ba2c57-8f55-4e9f-9606-c96d16b77892">
<img width="132" alt="Screenshot 2024-05-27 at 20 44 46"
src="https://github.com/go-gitea/gitea/assets/115237/0e838fb8-5e8c-4250-9843-a68b88d5418b">
<img width="80" alt="Screenshot 2024-05-27 at 20 44 33"
src="https://github.com/go-gitea/gitea/assets/115237/da6c7f83-c160-4389-8ab2-889d0568cbe8">
<img width="80" alt="Screenshot 2024-05-27 at 20 44 26"
src="https://github.com/go-gitea/gitea/assets/115237/cdb490b2-5040-484a-92e5-46fc5e37c199">
<img width="78" alt="Screenshot 2024-05-27 at 20 44 20"
src="https://github.com/go-gitea/gitea/assets/115237/d2978ab0-764e-41ff-922c-25f8fe749f28">

Would backport as trivial enhancement.

Co-authored-by: silverwind <me@silverwind.io>