Align pending-death XP logic and runtime config snapshot usage

[Copilot]

Static analysis highlighted a logic mismatch in XP handling and configuration reads that could cause inconsistent behavior across death-resolution paths. This PR consolidates those paths so runtime decisions use a single XP model and the active DKIConfig snapshot.

• XP handling parity in pending-death resolution

  • Standardized XP computation to calculateTotalExperience(savedLevel, savedExp) across grave and natural-drop fallback flows.
  • Removed fallback approximation logic that could diverge from stored pending-death state.

• Runtime config reads moved to snapshot

  • Replaced selected hot-path getConfig() reads with plugin.getDKIConfig() in core runtime components (DynamicKeepInvPlugin, IntegrationManager, CommandCompleter, CommandDispatcher, StatsGUI, PendingDeathManager).
  • Reduces mixed config-source behavior during runtime.

• Immediate snapshot refresh after command-driven config writes

  • After command enable/disable/toggle mutations, refreshDKIConfig() is called to keep command behavior and runtime state synchronized.

int xp = calculateTotalExperience(pending.getSavedLevel(), pending.getSavedExp());
if (xp > 0) {
    dropLocation.getWorld().spawn(dropLocation, ExperienceOrb.class, orb -> orb.setExperience(xp));
}