### Summary
- Adds some more checks in case a corpse's owner is somehow null. Would like to eventually allow null owner corpses, but more work is needed.
- Cleans up variable unboxing and reassignment in quests. Also flattens quest logic. Still more work needs to be done.
- Codegens more quest items/mobiles.
* Removes scaled speed by dex for monsters
* Changes scaled speed by dex for pets (HS+ expansion) to be 400ms -> 100ms between 50 -> 200 dex
* Removes speed changes that were broken for various mobs
* Combines "Legacy" speed and renames the class to `NPCSpeeds`
* Creates speed "classes" (slow, medium, fast, very fast)
* Introduces a new overridable property `SpeedClass`. Register a new speed class using `NPCSpeeds.Register()` and then set the speed class to bulk/mass apply speeds.
Order of speed determination:
1. SpeedMod
2. SpeedClass property (not null)
3. SpeedClass entry in Data\npc-speeds.json for that type
4. "Fast" (200ms Active, 400ms Passive)
* Adds the following configurations:
* `movement.delay.npcMinDelay` - 0.1 - Pets or Non-monster NPCs
* `movement.delay.npcMaxDelay` - 0.4 - Pets or Non-monster NPCs
* `movement.delay.monsterMinDelay` - 0.4 - Non-pet Monsters or NPC vs Player Combat
* `movement.delay.monsterMaxDelay` - 0.8 - Non-pet Monsters or NPC vs Player Combat
* `movement.delay.monsterMinDex` - 150 - Dex maximum for delay by dex
* `movement.delay.MinDex` - 190 - Dex maximum for delay by dex
