docs(go): clarify usage limits are included with subscription (anomalyco#15948)

Cherry-picked from upstream PR anomalyco#15948.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

Author: IgorTavcar

packages/web/src/content/docs/go.mdx

@@ -73,7 +73,7 @@ The list of models may change as we test and add new ones.
 
 ## Usage limits
 
-OpenCode Go includes the following limits:
+OpenCode Go includes the following rate limits to ensure fair access for all subscribers. These are **included** with your $10/month subscription and are not additional charges:
 
 - **5 hour limit** — $12 of usage
 - **Weekly limit** — $30 of usage