* Little's optimisations and booleans in conditions
* Apply strict type
* Apply strict type
* Apply strict type
* Fix multiple bugs with PHP 8.2 and 8.3
* Many declares missing, more errors fixed
* Apply strict type
* Another approach
* Stronger typing for Minz_Session
* Fix case of SQLite
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Co-authored-by: Luc <sanchezluc+freshrss@gmail.com>
Co-authored-by: Alexandre Alapetite <alexandre@alapetite.fr>
Even if the issue #3035 seemed pretty simple at a first glance, it was
more complicated than I expected. Because we send CSP headers AFTER
running the controller actions, it means we can't "echo" any content
from the controller. It's in fact a good practice, but it was easier at
the time we developed the feature.
To fix that, the only thing I had to do was to move the `print()` and
`readfile()` function into the view. The problem was that we needed to
output the content from the CLI too. Then, things became more
complicated. I decided to extract the export-related methods in a
`FreshRSS_Export_Service` class, in order to use it from both the
controller and the CLI. It was an opportunity to refactor the whole
feature in order to make it a bit more linear and easy to read.
Reference: https://github.com/FreshRSS/FreshRSS/issues/3035
