Change storage method for waypoints to support map markers

[claywar]

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• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

Closes #2808

• Changes index for storing unlocked waypoints to use 2x uint32 fields (from 5)
• Corrects issues with higher value indices from previous implementation
• Adds workaround for Western Adoulin waypoint NPC order

Steps to test these changes

Unlock various waypoints:

• City zones should correctly display unlocked waypoints, and teleport to appropriate locations
• Non-city zones should only allow transport to unlocked Eastern, Western Adoulin waypoints and unlocked waypoints in current zone