feat: Add OPML Import API

[SMillerDev]

• References: 25.0.0-alpha3: No export button anymore? #2541, feat: add import/export opml to user settings #2874

Summary

This adds an API that will take an OPML file as either a File upload with the name file, or as a request body.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Changelog entry added for all important changes.

[SMillerDev]

Since my environment is still broken I couldn't test this one either.
I wrote it completely based on documentation so I hope it works.

[wofferl]

Since my environment is still broken I couldn't test this one either. I wrote it completely based on documentation so I hope it works.

I got Caused by Error: Call to a member function has() on array at apps/news/lib/Controller/ImportController.php line 44 on a short test.

$this->request->files seems not to handled like an object and the content must probably be taken from the tmp file.
This is the content from $this->request->files:

{"file":{"name":"subscriptions-2024-11-17.opml","full_path":"subscriptions-2024-11-17.opml","type":"text/x-opml+xml","tmp_name":"/tmp/phpV79FAX","error":0,"size":1329}}

[wofferl]

this will work:

        $data = '';
        if (isset($this->request->files['file'])) {
            $file = $this->request->files['file'];
            $data = file_get_contents($file['tmp_name']);
        } else {
            $data = $this->request->getContent();
        }

[SMillerDev]

I gues I must have read the docs for a wrong version of symfony? Let's use your version.

[wofferl]

All we need now for the importer is the handling of duplicate and incorrect feeds.

The importer currently still aborts in $this->feedService->create on the first problem (existing or faulty feed).

The existing fee could be handled with an extra check in OpmlService.php before the create. But for the faulty ones we would have to do an extra handling, if we want to add them. Possibly a create without initial fetch.

[SMillerDev]

I really don't want to add faulty feeds. Those should really error out iyam. For duplication, I guess we'll have to do some checking.