P1B: Refactor (<src/topics/posts.js:80>): <Function with high complexity (count = 30): addEventStartEnd>

### Uniqueness check

- [x] I have searched open issues and confirmed this **file + smell** is not already taken.

### Full path to the JavaScript file

src/topics/posts.js

### Function(s)/scope targeted

addEventStartEnd(...)

### Relevant Qlty output

```shell
80  Function with high complexity (count = 30): addEventStartEnd
```