Describe the bug

Hey, thank you for all your work. I noticed that when adding multiple feeds in a single request it's not possible to assign a category to both. For example, only the 2nd feed will be assigned to testtag2 (the 1st feed will be uncategorized) given the following:

curl 'https://rss.mysite.com/api/greader.php/reader/api/0/subscription/edit' \
  --data-raw 'ac=subscribe&s=feed%2Fhttps%3A%2F%2Ffeeds.arstechnica.com%2Farstechnica%2Ftechnology-lab&t=ars+techlab&a=user%2F-%2Flabel%2Ftesttag1&s=feed%2Fhttps%3A%2F%2Ffeeds.arstechnica.com%2Farstechnica%2Fgadgets&t=ars+gadets&a=user%2F-%2Flabel%2Ftesttag2'

Same behavior if only one a param is sent.

To Reproduce

cURL provided above

Expected behavior

Ideally, the a (category) param would be treated as an array, similar to $streamNames and $titles. I suppose the next best thing would be to at least be able to apply a single category to all feeds in the request, though that feels a bit inconsistent.

FreshRSS version

1.24.3

Environment information

• Installation type: Docker

Additional context

No response