sidebar: Set tooltip of room rows
(Warning: this was not even compile-tested, as Fractal Devel doesn't build due to matrix-rust-sdk requiring a more recent Rust version)
Room names can be large in some circumstances. Usually in dynamic lists like this, where the textual content can be unpredictable, adding a tooltip text is helpful.
Add that.
Edited by Georges Basile Stavracas Neto