fix(opencode): inherit user-selected models

.opencode/README.md

@@ -224,8 +224,6 @@ Full configuration in `opencode.json`:
 ```json
 {
   "$schema": "https://opencode.ai/config.json",
-  "model": "anthropic/claude-sonnet-4-5",
-  "small_model": "anthropic/claude-haiku-4-5",
   "plugin": ["./plugins"],
   "instructions": [
     "skills/tdd-workflow/SKILL.md",
@@ -236,6 +234,10 @@ Full configuration in `opencode.json`:
 }
 ```
 
+The reference config intentionally leaves model selection to OpenCode. Connect a
+provider and select a model in OpenCode; ECC's primary agent uses that global
+selection, and its subagents inherit the invoking primary agent's model.
+
 ## License
 
 MIT