[TOOLS][DOCS] Add missing doc blocks

src/Controller/UserPanel.php

@@ -187,6 +187,9 @@ class UserPanel extends Controller
         return $form;
     }
 
+    /**
+     * Controller for defining the ordering of a users's languages
+     */
     public function sortLanguages(Request $request)
     {
         $user = Common::ensureLoggedIn();

src/Core/Cache.php

@@ -320,6 +320,11 @@ abstract class Cache
         }
     }
 
+    /**
+     * Fetch the value(s) for key $key in the hashmap identified by
+     * $map_key. If not found, use $calculate_map to calculate the
+     * _entire_ hashmap (not just those in $key)
+     */
     public static function getHashMapKey(string $map_key, string|array $key, callable $calculate_map, string $pool = 'default')
     {
         if (isset(self::$redis[$pool])) {

src/Util/Form/FormFields.php

@@ -16,6 +16,9 @@ use Symfony\Component\Validator\Constraints\NotBlank;
 
 abstract class FormFields
 {
+    /**
+     * Create a form field for asking for a new password twice (ensuring they're the same)
+     */
     public static function repeated_password(array $options = []): array
     {
         $constraints = ($options['required'] ?? true)
@@ -53,6 +56,8 @@ abstract class FormFields
     }
 
     /**
+     * Create a form field for asking for an existing password
+     *
      * @codeCoverageIgnore
      */
     public static function password(array $options = []): array
@@ -72,6 +77,9 @@ abstract class FormFields
         ];
     }
 
+    /**
+     * Create a from field for `select`ing a language for $actor, in reply or related to $context_actor
+     */
     public static function language(Actor $actor, ?Actor $context_actor, string $label, ?string $help = null, bool $multiple = false, bool $required = true, ?bool $use_short_display = null): array
     {
         [$language_choices, $preferred_language_choices] = Language::getSortedLanguageChoices($actor, $context_actor, use_short_display: $use_short_display);