fixes #1406

Update Arch Linux installation instructions

nheko Arch Linux package is now available in community repository, AUR
isn't needed anymore to install it.

Currently translated at 100.0% (942 of 942 strings)

Co-authored-by: Chen Shaoju <oshirisu.red@gmail.com>
Translate-URL: https://weblate.nheko.im/projects/nheko/nheko-master/zh_Hans/
Translation: Nheko/nheko

Currently translated at 47.8% (451 of 942 strings)

Co-authored-by: NullPointerException <kigen745@gmail.com>
Translate-URL: https://weblate.nheko.im/projects/nheko/nheko-master/uk/
Translation: Nheko/nheko

Create github release from tags and upload artifacts as assets

README.md: fix link of stable download badge

Since this causes crashes on some qml module updates.

Fixes #1383
Fixes #1132

Delete some unneeded stuff

fixes #1355

So far we haven't seen any reduction in issues about database
corruption, so presumably this is unrelated and the lag is annoying.

Blur images properly

support OpenBSD

Instead of completing the list of Linux, Windows and the BSDs (NetBSD and
DragonFly would still be missing), simply flip it to not-macOS to simplify
and fix the two other aforementioned BSDs at once.

CMake builds ManagerLinux.cpp on `!MAC && !WIN`, that is BSD and Linux.
Fix the Linux-only assumption in the shared header.

Qt's `Q_OS_UNIX` is defined on Linux, BSDs and macOS alike.

print errors on failed dialog creation

Signed-off-by: Marcus Hoffmann <bubu@bubu1.eu>