Upgrade to PHP 8.1 (#6711)

* Upgrade to PHP 8.1
As discussed in https://github.com/FreshRSS/FreshRSS/discussions/5474

https://www.php.net/releases/8.0/en.php
https://www.php.net/releases/8.1/en.php

Upgrade to available native type declarations
https://php.net/language.types.declarations

Upgrade to https://phpunit.de/announcements/phpunit-10.html which requires PHP 8.1+ (good timing, as version 9 was not maintained anymore)

Upgrade `:oldest` Docker dev image to oldest Alpine version supporting PHP 8.1: Alpine 3.16, which includes PHP 8.1.22.

* Include 6736
https://github.com/FreshRSS/FreshRSS/pull/6736

1 files changed, 6 insertions, 16 deletions

diff --git a/p/api/fever.php b/p/api/fever.php
index 77d778305..5ddfba269 100644
--- a/p/api/fever.php
+++ b/p/api/fever.php
@@ -426,33 +426,29 @@ final class FeverAPI
 
 	/**
 	 * @param numeric-string $id
-	 * @return int|false
 	 */
-	private function setItemAsRead(string $id) {
+	private function setItemAsRead(string $id): int|false {
 		return $this->entryDAO->markRead($id, true);
 	}
 
 	/**
 	 * @param numeric-string $id
-	 * @return int|false
 	 */
-	private function setItemAsUnread(string $id) {
+	private function setItemAsUnread(string $id): int|false {
 		return $this->entryDAO->markRead($id, false);
 	}
 
 	/**
 	 * @param numeric-string $id
-	 * @return int|false
 	 */
-	private function setItemAsSaved(string $id) {
+	private function setItemAsSaved(string $id): int|false {
 		return $this->entryDAO->markFavorite($id, true);
 	}
 
 	/**
 	 * @param numeric-string $id
-	 * @return int|false
 	 */
-	private function setItemAsUnsaved(string $id) {
+	private function setItemAsUnsaved(string $id): int|false {
 		return $this->entryDAO->markFavorite($id, false);
 	}
 
@@ -538,18 +534,12 @@ final class FeverAPI
 		return $beforeTimestamp == 0 ? '0' : $beforeTimestamp . '000000';
 	}
 
-	/**
-	 * @return int|false
-	 */
-	private function setFeedAsRead(int $id, int $before) {
+	private function setFeedAsRead(int $id, int $before): int|false {
 		$before = $this->convertBeforeToId($before);
 		return $this->entryDAO->markReadFeed($id, $before);
 	}
 
-	/**
-	 * @return int|false
-	 */
-	private function setGroupAsRead(int $id, int $before) {
+	private function setGroupAsRead(int $id, int $before): int|false {
 		$before = $this->convertBeforeToId($before);
 
 		// special case to mark all items as read