Effect model additive blend, teleport facing, tighter area triggers

Classify light shafts, portals, spotlights, bubbles, and similar M2
doodads as spell effects so they render with additive blending instead
of as solid opaque objects.

Set camera yaw from server orientation on world load so teleports face
the correct direction.

Reduce area trigger minimum radius (3.0 sphere, 4.0 box) to prevent
premature portal firing near tram entrances.

src/game/game_handler.cpp

@@ -8814,16 +8814,16 @@ void GameHandler::checkAreaTriggers() {
 
         bool inside = false;
         if (at.radius > 0.0f) {
-            // Sphere trigger — small minimum so player must be near the portal
-            float effectiveRadius = std::max(at.radius, 12.0f);
+            // Sphere trigger — use actual radius, with small floor for very tiny triggers
+            float effectiveRadius = std::max(at.radius, 3.0f);
             float dx = px - at.x;
             float dy = py - at.y;
             float dz = pz - at.z;
             float distSq = dx * dx + dy * dy + dz * dz;
             inside = (distSq <= effectiveRadius * effectiveRadius);
         } else if (at.boxLength > 0.0f || at.boxWidth > 0.0f || at.boxHeight > 0.0f) {
-            // Box trigger — small minimum so player must walk into the portal area
-            float boxMin = 16.0f;
+            // Box trigger — use actual size, with small floor for tiny triggers
+            float boxMin = 4.0f;
             float effLength = std::max(at.boxLength, boxMin);
             float effWidth = std::max(at.boxWidth, boxMin);
             float effHeight = std::max(at.boxHeight, boxMin);