Add TTS on ios

[ztefanie]

Is your feature request related to a problem? Please describe.
As a analphabetic user/less fluent reader I want to have the possibility to get texts read out loud such that I can still use the app and understand the content. This feedback was given the target group contact team

Describe the solution you'd like
Add an option in the UI to read the current text: See design here
This should work for categories
It should work in all supported languages (if possible)

Leading platforms prioritize accessibility and user control over imposing character-based restrictions. I would recommend making the tts functionality available for all third level pages, providing a consistent experience for our users.

We may use these libraries "React-Native: https://www.npmjs.com/package/react-native-tts" or try to directly communicate with the OS-TTS engines. Select the solution that works better / can be implemented easier.

• We only read texts of third level categories
• target group for this feature are people with basic reading skills and/or basic language skills, not for people who cannot read at all
• we aim to use the native build in tts functionality
• should be available offline
• should support multiple languages, we may need to navigate to settings where the content language can be downloaded. if language is not available we use the device language and do not disable the feature
• we do not want to read "lists with 3 elements" or stuff like this. We expect user to have basic reading skills and read the text while the tts reads it.
• we aim to support web and native, but we will start with native
• pausing should be possible
• we want to have this feature enabled by default, but design should not be annoying for people who do not want to this feature or add an easy way to turn it off / hide it.
• this feature should only be available for integreat, not for malte or aschaffenburg

Additional context

• See discussion this "meta/story" issue [Meta] Text to speech (TTS) #2821
• See additional information on the motiviation here