feat(starter): add Brave search to tool groups

- Add builtin::websearch_brave to default_tool_groups in starter.py
- Regenerate run.yaml with distro codegen
- Fixes #2606: Brave search was configured but not registered

Following template architecture pattern:
- Modified template source (starter.py)
- Used distro codegen to regenerate config files
- Never edited generated files directly

llama_stack/templates/starter/run.yaml

@@ -1196,6 +1196,8 @@ benchmarks: []
 tool_groups:
 - toolgroup_id: builtin::websearch
   provider_id: tavily-search
+- toolgroup_id: builtin::websearch_brave
+  provider_id: brave-search
 - toolgroup_id: builtin::rag
   provider_id: rag-runtime
 server:

llama_stack/templates/starter/starter.py

@@ -347,6 +347,10 @@ def get_distribution_template() -> DistributionTemplate:
             toolgroup_id="builtin::websearch",
             provider_id="tavily-search",
         ),
+        ToolGroupInput(
+            toolgroup_id="builtin::websearch_brave",
+            provider_id="brave-search",
+        ),
         ToolGroupInput(
             toolgroup_id="builtin::rag",
             provider_id="rag-runtime",