fix(memory): keep llama runtime optional (#71425)

* fix(memory): keep llama runtime optional

* fix(memory): harden optional llama runtime guard

docs/concepts/memory-builtin.md

@@ -38,8 +38,9 @@ To set a provider explicitly:
 
 Without an embedding provider, only keyword search is available.
 
-To force the built-in local embedding provider, point `local.modelPath` at a
-GGUF file:
+To force the built-in local embedding provider, install the optional
+`node-llama-cpp` runtime package next to OpenClaw, then point `local.modelPath`
+at a GGUF file:
 
 ```json5
 {
@@ -66,7 +67,7 @@ GGUF file:
 | Voyage   | `voyage`  | Yes           |                                     |
 | Mistral  | `mistral` | Yes           |                                     |
 | Ollama   | `ollama`  | No            | Local, set explicitly               |
-| Local    | `local`   | Yes (first)   | GGUF model, ~0.6 GB download        |
+| Local    | `local`   | Yes (first)   | Optional `node-llama-cpp` runtime   |
 
 Auto-detection picks the first provider whose API key can be resolved, in the
 order shown. Set `memorySearch.provider` to override.

docs/concepts/memory-qmd.md

@@ -15,7 +15,8 @@ binary, and can index content beyond your workspace memory files.
 - **Reranking and query expansion** for better recall.
 - **Index extra directories** -- project docs, team notes, anything on disk.
 - **Index session transcripts** -- recall earlier conversations.
-- **Fully local** -- runs via Bun + node-llama-cpp, auto-downloads GGUF models.
+- **Fully local** -- runs with the optional node-llama-cpp runtime package and
+  auto-downloads GGUF models.
 - **Automatic fallback** -- if QMD is unavailable, OpenClaw falls back to the
   builtin engine seamlessly.
 

docs/concepts/memory-search.md

@@ -29,8 +29,8 @@ explicitly:
 }
 ```
 
-For local embeddings with no API key, use `provider: "local"` (requires
-node-llama-cpp).
+For local embeddings with no API key, install the optional `node-llama-cpp`
+runtime package next to OpenClaw and use `provider: "local"`.
 
 ## Supported providers