[Zoning] Improve zone routing

[Akkadius]

Description

This PR is necessary to fix a few reported extreme edge cases. It simplifies the routing logic quite a bit. This logic has otherwise been battle tested for a few months now with little to no issues.

• Using #zoneinstance to a public static instance and being able to not zone
• Rare chance that the wrong zone data gets matched with an instance route
• We no longer route players when they matched a zone but didn't match an instance, this is something that should be handled by the rest of the code and normally be returned as zone_id 0 so zoning can continue as normal. This also created the possibility that the wrong zone data could be used in the route.
• Use zone data from zone_store and reload zone_store data when issuing content_flag data reloads instead of holding a copy of our own zones.

The code now ensures that if the zone in question is an instance, that we match explicitly the instance_id when we are iterating through public static instances. Before, there was a rare chance that the wrong instance could be matched if multiples of the same were in the database.

WorldContentService::FindZoneResult WorldContentService::FindZone(uint32 zone_id, uint32 instance_id)
{
	for (const auto &z: zone_store.GetZones()) {
		for (auto &i: m_zone_static_instances) {
			if (
				z.zoneidnumber == zone_id &&
				DoesZonePassContentFiltering(z) &&
				i.zone == zone_id &&
				i.version == z.version) {

				if (instance_id > 0 && i.id != instance_id) {
					continue;
				}

				LogInfo(
					"Routed player to public static instance [{}] of zone [{}] ({}) version [{}] long_name [{}] notes [{}]",
					i.id,
					z.short_name,
					z.zoneidnumber,
					z.version,
					z.long_name,
					i.notes
				);

				return WorldContentService::FindZoneResult{
					.zone_id = static_cast<uint32>(z.zoneidnumber),
					.instance = i,
					.zone = z
				};
			}
		}
	}

	return WorldContentService::FindZoneResult{.zone_id = 0};
}

// FindZone handles content and context aware zone routing (middleware)
//
// this is a middleware function that is meant to be used in the zone change process
// this hooks all core zone changes within the server and routes the player to the correct zone
// returning a zone_id of non-zero means the middleware will route the player
// returning a zone_id of 0 means the middleware will not route the player
// this is useful for handling multiple versions of the same zone
//
// implementation >
// the zoning and process spawning logic already is handled by two keys "zone_id" and "instance_id"
// we leverage static, never expires instances to handle this and client still sees it as a normal zone
//
// content awareness >
// simply use the zone_id, server content settings and the middleware will handle the rest
// you don't have to think about instances in any data tables (use instance_id 0)
// you don't have to keep track of instance ids in scripts (use instance_id 0)
// the versions of zones are represented by two zone entries that have potentially different min/max expansion and/or different content flags
// we decide to route the client to the correct version of the zone based on the current server side expansion
//
// example >
// we want to route players to the correct version of lavastorm based on the current server side expansion (DoesZonePassContentFiltering)
// lavastorm (pre-don) version 0 (classic)
//   zone table entry for version = 0, min_expansion = 0, max_expansion = 8
//   instance_list table entry for lavastorm has version = 0, is_global = 1, never_expires = 1
// lavastorm (don) version 1
//   zone table entry for version = 1, min_expansion = 9, max_expansion = 99
//   instance_list table entry for lavastorm has version = 1, is_global = 1, never_expires = 1

Type of change

• Bug fix (non-breaking change which fixes an issue)

Testing

Tested zoning locally

Checklist

• I have tested my changes
• I have performed a self-review of my code. Ensuring variables, functions and methods are named in a human-readable way, comments are added only where naming of variables, functions and methods can't give enough context.
• I own the changes of my code and take responsibility for the potential issues that occur

[Akkadius]

@fryguy503 will have this sitting on his server soon too to test

[fryguy503]

Coupled with PR #4429 This has been working well.