Add VolumeObject trigger target type for direct volume control

[Copilot]

Adds VolumeObject trigger target type to enable direct enable/disable control of volume instances in TombEngine, distinct from VolumeEvent which triggers event sets associated with volumes.

Changes

• TriggerInstance.cs: Added VolumeObject = 18 to TriggerTargetType enum
• NgParameterInfo.cs: Exposed VolumeObject target type and VolumesInLevel parameter range for TombEngine
• NgParameterRange.cs: Implemented VolumesInLevel support for volume instance selection in UI
• LevelCompilerTombEngine.cs: Added _volumeTable for global volume indexing across rooms
• FloorData.cs: Implemented VolumeObject compilation with TryGetValue error handling

Implementation

Volumes are indexed globally during compilation, similar to cameras and sinks. Triggers store the volume index in compiled floor data:

// Volume table populated at compile time
_volumeTable = new Dictionary<VolumeInstance, int>();
foreach (var room in _level.ExistingRooms)
    foreach (var obj in room.Objects.OfType<VolumeInstance>())
        _volumeTable.Add(obj, volumeID++);

// Trigger compilation groups VolumeObject with other simple object triggers
case TriggerTargetType.VolumeObject:
    trigger2 = (ushort)(GetTriggerParameter(trigger.Target, trigger, _fdFunctionMask) | func);
    result.Add(trigger2);

Game engine can now reference volumes by index to control their enabled state via trigger actions.

Original prompt

I want to add new trigger object type. It should be for volume object.

Once its compiled in level data I can easily add code to enable, disable volume object in the game engine using triggers.

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