[Shared Tasks] Implement Activity Locking (#2339)

* Add shared task element locking

This adds the `lock_activity_id` field to the tasks table which will
automatically lock a shared task when that element becomes active.

A method was added to world analogous to zone's UnlockActivities to
determine when an activity is active with respect to task steps.

Also adds quest apis to manually lock or unlock a client's shared task

* Add comment

utils/sql/db_update_manifest.txt

@@ -445,6 +445,7 @@
 9189|2022_07_10_character_task_rewarded.sql|SHOW COLUMNS FROM `character_tasks` LIKE 'was_rewarded'|empty|
 9190|2022_07_13_task_reward_points.sql|SHOW COLUMNS FROM `tasks` LIKE 'reward_points'|empty|
 9191|2022_07_28_gm_state_changes.sql|SHOW COLUMNS FROM `account` LIKE 'invulnerable'|empty|
+9192|2022_07_13_task_lock_activity.sql|SHOW COLUMNS FROM `tasks` LIKE 'lock_activity_id'|empty|
 
 # Upgrade conditions:
 # 	This won't be needed after this system is implemented, but it is used database that are not

utils/sql/git/required/2022_07_13_task_lock_activity.sql

@@ -0,0 +1,2 @@
+ALTER TABLE `tasks`
+  ADD COLUMN `lock_activity_id` INT NOT NULL DEFAULT '-1' AFTER `request_timer_seconds`;