Added window role to image overlay

Might be unnecessary, but docs are unclear on that.

fixes #435

fixes #351

fixes #529

fixes #817
fixes sidebar not staying small after restart

fixes #824

fixes #519

fixes #840

Currently translated at 100.0% (612 of 612 strings)

Co-authored-by: Linerly <linerly@protonmail.com>
Translate-URL: https://weblate.nheko.im/projects/nheko/nheko-master/id/
Translation: Nheko/nheko

Allows access to spaces on mobile for example

Currently translated at 100.0% (612 of 612 strings)

Co-authored-by: Jaron Viëtor <jaron@v8or.nl>
Translate-URL: https://weblate.nheko.im/projects/nheko/nheko-master/nl/
Translation: Nheko/nheko

Go through some CLion (clazy, clang-tidy) suggestions in InputBar{cpp.h}

Currently translated at 99.8% (611 of 612 strings)

Co-authored-by: Tirifto <tirifto@posteo.cz>
Translate-URL: https://weblate.nheko.im/projects/nheko/nheko-master/eo/
Translation: Nheko/nheko

Currently translated at 100.0% (612 of 612 strings)

Co-authored-by: Eldred HABERT <stuff@eldred.fr>
Translate-URL: https://weblate.nheko.im/projects/nheko/nheko-master/fr/
Translation: Nheko/nheko

This warns when you the return value of those functions isn't used.

Suggested-by: Clang-Tidy: Function X should be marked [[nodiscard]]

Suggested-By:

Clang-Tidy: Single-argument constructors must be marked explicit to
avoid unintentional implicit conversions

More info: https://clang.llvm.org/extra/clang-tidy/checks/google-explicit-constructor.html

Suggested-by:

Clang-Tidy: The 'empty' method should be used to check for emptiness instead of 'size'