A Complete Whitelist Module

[NotSoDelayed]

Problem

Skript is lacking certain coverage on whitelist related APIs, especially whitelist events.

Solution

This PR focuses more on completing the whitelist module, such as:

• Adds missing events: server and player whitelist events
• Adds a condition to check the whitelist state for whitelist events
• Optimizes on existing whitelist syntaxes for current Skript code standards
• Migrates current (as of this PR) and existing whitelist syntaxes into Skript's registration API

Testing Completed

The current test coverage for whitelist only covers manipulating player list in whitelist and server whitelist state. Alongside with new additions added in this PR, JUnit tests were also added -- in EvtWhitelistTest.java and EvtWhitelistTest.sk, marking this a complete test coverage specifically for whitelist.

Supporting Information

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Completes: none Related: none

[NotSoDelayed]

PS. MC 1.19.4 tests are expected to fail due to classes doesn't exist in that version, but the next Skript release drops support of that version