[SAK-FEA-6] Add settings

[anafro]

Issue information

• Sakurator last version when issue was suggested: 1.0.0.37
• Type: feature

Why this feature should be added?

Customisation is must-have on services like Sakurator. So, in the settings should be:

• Audio settings, such as volume of AFX, letter pronunciation volume, etc.
• Dark mode
• Visual effects (petal count and animations)

Difficulty for me

Settings should be saved somewhere. I think that UI settings should not be the same for each device, so they can be saved in cookies. But other settings can force me to implement an auth system

Probable issues

So, no, I cannot predict any issue yet that can come with this feature.