Make some CoreExtension methods part of the public API

CHANGELOG

@@ -1,5 +1,7 @@
 # 3.10.0 (2024-XX-XX)
 
+ * Make `CoreExtension::formatDate`, `CoreExtension::convertDate`, and
+   `CoreExtension::formatNumber` part of the public API
  * Add `needs_charset` option for filters and functions
  * Extract the escaping logic from the `EscapingExtension` class to a new
    `EscapingRuntime` class.

src/Extension/CoreExtension.php

@@ -413,8 +413,6 @@ final class CoreExtension extends AbstractExtension
      * @param \DateTimeInterface|\DateInterval|string $date     A date
      * @param string|null                             $format   The target format, null to use the default
      * @param \DateTimeZone|string|false|null         $timezone The target timezone, null to use the default, false to leave unchanged
-     *
-     * @internal
      */
     public function formatDate($date, $format = null, $timezone = null): string
     {
@@ -479,8 +477,6 @@ final class CoreExtension extends AbstractExtension
      * @param \DateTimeZone|string|false|null $timezone The target timezone, null to use the default, false to leave unchanged
      *
      * @return \DateTime|\DateTimeImmutable
-     *
-     * @internal
      */
     public function convertDate($date = null, $timezone = null)
     {
@@ -583,8 +579,6 @@ final class CoreExtension extends AbstractExtension
      * @param int|null    $decimal      the number of decimal points to display
      * @param string|null $decimalPoint the character(s) to use for the decimal point
      * @param string|null $thousandSep  the character(s) to use for the thousands separator
-     *
-     * @internal
      */
     public function formatNumber($number, $decimal = null, $decimalPoint = null, $thousandSep = null): string
     {