docs: point consumers to adapter seam / 文件明確導向 adapter seam

INTEGRATION.md

@@ -53,11 +53,20 @@ At minimum, verify these behaviors in Telegram:
 
 - `src/adapters/openclaw.ts`
 - `src/adapters/openclaw-state-file.ts`
+- `src/adapters/openclaw-message-tool.ts`
+- `src/adapters/openclaw-interactive-handler.ts`
+- `src/adapters/openclaw-plugin-skeleton.ts`
 - `src/runtime/openclaw-telegram-bridge.ts`
 - `src/runtime/openclaw-telegram-poc.ts`
 
 These do not yet replace the runtime patch end-to-end, but they are the current repo-side ownership points for the logic.
 
+Current preferred future seam:
+
+- `src/adapters/openclaw-plugin-skeleton.ts`
+
+This is the clearest current approximation of where a cleaner formal plugin-facing integration path should grow.
+
 ## Known limitation
 
 The current integration path is reproducible, but not yet clean enough to call a final plugin package.