[Vitorinox]

Patch release fixes. No new public API.

• X/Twitter (Twitter extractor will retrieve "/home" instead of a tweet URL #520, Twitter.com to X.com migration giving errors #536): the Twitter adapter gets its own oEmbed class that always asks publish.twitter.com/oembed for the status URL that was requested (twitter.com, x.com, www., mobile., /status/ or /statuses/, query string dropped), instead of the page reached after redirects (x.com/home, x.com/x/migrate, login wall). The title falls back to "Tweet by {author}" instead of "x.com".
• HTML title encoding issue #372: clean() keeps a < followed by a digit, space or = (like =<250A), so strip_tags() no longer drops the rest of the text.
• Removed double spaces #485: url() reads the raw value, so inner spaces in image URLs are kept and encoded as %20 instead of collapsed.
• wrong extracted data when fetching image link behind redirect #524: media detected by content type (images behind redirects) use the final URL as src.
• Awesome library, but it keeps files open #283: on PHP 8 the curl callbacks kept a reference cycle to the dispatcher, so handles and their file descriptors stayed open until the GC ran. They are replaced with static closures when the request finishes. Includes a test that counts open file descriptors.

Tests use fake responses only (no network). PHPUnit passes on PHP 7.4, 8.1, 8.2, 8.3, 8.4 and 8.5, and PHPStan reports no errors.

Not included: #552 (already fixed in 4.4.18), #539 (cookies already use a single embed-cookies.txt or the cookies_path setting), #509 (the reported page declares windows-1251 and is extracted correctly; guessing a charset for pages that declare none is out of scope for a patch).

Fixes #520
Fixes #536
Fixes #372
Fixes #485
Fixes #524
Fixes #283