[Feature]: Shareable shelves

[lbird-mma]

✨ Feature Request for Booklore

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📝 Description

I'm using a Booklore instance with multiple users. I like to make a shared shelf, just like the Unshelved shelf is a shared list. I tried creating a new shelf, but it's not visible by other users.

🌟 Benefits

Books can be "exchanged" or spotlighted, shared on shelves etc

💻 Use Cases

1. For example if I have read a book I really like, I want to shelve it on a "Spotlight" shelf, so other users can see my book tip.

📸 Visual References (Optional)

🎨 Technical Details (Optional)

📌 Additional Context

[lbird-mma]

Solved in #1662 ?

[lbird-mma]

Before, this one seemed solved in #1662 but until now it hasn't been merged. Any reason for that?