OClCollMeshEngn: produce ambience into stimBuff frames directly

docs/design/stencils.md

@@ -77,14 +77,18 @@ raising new intrins.
 - Stimbuffs must respect this limit and wait for stencil returns before
   allocating new ones
 
-**Example:**
+**Example (generic device):**
+```
++idev|my-device|someQualeApi(n-stencils=4)|someStimBuffApi()|livoxProto1()|SERIAL
+```
+
+The `pcloudAmbience` Livox Gen1 path does **not** use the `n-stencils` parameter; ambience data is delivered as a dense float vector in the stimulus frame buffer, not via a separate stencil allocation list.
+
+**Deprecated example (do not use for Livox Gen1 ambience):**
 ```
 +idev|my-device|pcloudAmbience(n-stencils=4)|livoxGen1-pcloud()|livoxProto1()|3JEDK380010Z39
 ```
 
-This example allows the stimbuff to allocate up to 4 stencils
-simultaneously.
-
 ## Notes
 
 The stencil registration mechanism discussed above is not currently