feat: Jobs/Tasks + Moderation Overhaul

[sustained]

PR

• [x] Rename jobs to tasks
• [x] Add services/tasks - Persist task options/configuration
  • [x] If the DB is empty, create it based on the defaults in the task classes
  • [x] If a new task is created, add it to the DB
• [x] Add !error command, necessary for testing tasks/log
• [x] Refactor ban-words service to moderation service - supports various different actions
• [x] Add commands for managing moderation triggers
  • [x] !add-trigger <action=warn|kick|ban|notify> <trigger> - Add a trigger word/phrase
  • [x] !remove-trigger <trigger> - Remove a trigger word/phrase
  • [x] !list-triggers - List all triggers
• [x] Update/improve commands for managing tasks
  • [x] !enable-task <task-name> - Enable a task
  • [x] !disable-task <task-name> - Disable a task
  • [x] !task-info <task-name> - Show in-depth information about a task
  • [x] !list-tasks - Show all tasks and their status (enabled/disabled)
  • [x] !reset-tasks - Reset all tasks to their default configurations
• [x] Improve tasks
  • [x] LogTask
  • [x] Logs various events (command errors, unknown commands, successful invocations etc.)
  • [x] All is configurable (which things should be logged and where)
  • [x] BanTask -> ModerationTask
  • [x] Refactor to ModerationTask - now supports kicks, bans, warns & notifications
• [x] Add Task argument type
• [x] General refactoring
  • [x] Various improvements (inc. comments) to task- and moderation-related files
  • [x] Several iterations of misc. code clean up (DRY etc.)

Miscellaneous

I need to stop doing miscellaneous changes in random PRs, I know. But if I see an issue my immediate instinct is just to fix it there and then. :frowning:

• [x] Fix NODE_ENV issue.
• [x] Fix development-only commands in production.
• [x] Fix some unnecessary duplication in constants files.
• [x] Fix a small issue with trySend message util.