feat(vibegame): add terrain, audio assets and batch setup for simple-rpg

Add 2048x2048 terrain heightmap (10km world, seed 42) with terrain.json metadata. Update index.html with terrain config (levels=4, 16x16 chunks), spawn groups, camera and lighting. Add 8 generated audio SFX (hero, goblin, slime, merchant, potions, sword, shield, chest). Add batch scripts and presets-local.yaml for asset generation.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

Author: maikramer

VibeGame/examples/simple-rpg/index.html

@@ -38,7 +38,7 @@
       <!-- Fill + sol: mais fill no hemisfério + sol um pouco mais alto = sombras mais curtas e terreno menos “enterrado”. -->
       <GameObject
         ambient-light="sky-color: 0xd8ecff; ground-color: 0x726a58; intensity: 0.84"
-        directional-light="color: 0xfff8f2; intensity: 1.78; direction-x: -0.92; direction-y: 1.55; direction-z: -0.78; cast-shadow: 1; shadow-map-size: 4096; distance: 55"
+        directional-light="color: 0xfff8f2; intensity: 1.78; direction-x: -0.92; direction-y: 1.55; direction-z: -0.78; cast-shadow: 1; shadow-map-size: 4096; distance: 120"
       >
       </GameObject>
 
@@ -83,31 +83,31 @@
         spatial="false"
       ></AudioSource>
 
-      <!-- Relva: tom um pouco mais claro para ler melhor nas sombras (sem mexer no motor). -->
+      <!-- 10 km × 10 km terrain — 16×16 chunks (levels=4), 2048×2048 heightmap. -->
       <Terrain
         pos="0 0 0"
-        world-size="768"
-        max-height="28"
-        levels="6"
-        resolution="64"
-        lod-hysteresis="1.25"
+        world-size="10000"
+        max-height="200"
+        levels="4"
+        resolution="128"
+        lod-hysteresis="1.3"
         lod-distance-ratio="2"
-        height-smoothing="0.22"
-        height-smoothing-spread="1.15"
+        height-smoothing="0.3"
+        height-smoothing-spread="1.25"
         heightmap="/assets/terrain/heightmap.png"
-        collision-resolution="32"
+        collision-resolution="64"
         skirt-width="0.015625"
-        roughness="0.5"
+        roughness="0.85"
         metalness="0"
-        normal-strength="0.5"
+        normal-strength="0.6"
         base-color="#96ad78"
       ></Terrain>
 
       <!-- Água gerada dinamicamente a partir de /assets/terrain/terrain.json no bootstrap. -->
 
       <Fog
         color="#dde6d4"
-        density="0.001"
+        density="0.00025"
         mode="exponential"
         height-falloff="0.48"
         base-height="0"
@@ -118,7 +118,7 @@
 
       <PlayerGLTF
         name="hero"
-        pos="210 75 185"
+        pos="5000 250 5000"
         model-url="/assets/models/hero.glb"
         script="auto-attacker.ts"
       ></PlayerGLTF>
@@ -127,7 +127,7 @@
 
       <!-- Pós: nítido primeiro (sem CA); bloom/grain/vignette moderados — o pacote “AAA” anterior é que “desfocava”. -->
       <FollowCamera
-        target-distance="7"
+        target-distance="12"
         target-pitch="0.32"
         yaw-smoothness="0.055"
         position-lag="0.18"
@@ -143,10 +143,10 @@
       <!-- Pilares Y-up (GLB corrigido com scripts/fix-glb-yup-feet.py); só euler 0 no spawn. -->
       <SpawnGroup
         profile="tree"
-        count="30"
+        count="80"
         seed="11"
-        region-min="-330 0 -330"
-        region-max="330 0 330"
+        region-min="1000 0 1000"
+        region-max="9000 0 9000"
         max-slope-attempts="180"
         pick-strategy="random"
         scale-min="1.5"
@@ -165,10 +165,10 @@
 
       <SpawnGroup
         profile="gltf-crate"
-        count="30"
+        count="60"
         seed="23"
-        region-min="-280 0 -280"
-        region-max="280 0 280"
+        region-min="1500 0 1500"
+        region-max="8500 0 8500"
         max-slope-attempts="120"
         pick-strategy="random"
       >
@@ -182,13 +182,12 @@
         ></GLTFDynamic>
       </SpawnGroup>
 
-      <!-- ~660×660 m² → ~0,436 km²; 200 obj/km² → ~87 árvores (ajusta density-per-km2). Escala 1,5–4× linear; yaw só em múltiplos de 45°. -->
       <SpawnGroup
         profile="tree"
-        density-per-km2="200"
+        density-per-km2="60"
         seed="7"
-        region-min="-330 0 -330"
-        region-max="330 0 330"
+        region-min="0 0 0"
+        region-max="10000 0 10000"
         max-slope-attempts="220"
         pick-strategy="random"
         scale-min="1.5"