docs: remove obsolete vouch system section (#40266)

CONTRIBUTING.md

@@ -252,33 +252,6 @@ These are not strictly enforced, they are just general guidelines:
 
 For net-new functionality, start with a design conversation. Open an issue describing the problem, your proposed approach (optional), and why it belongs in OpenCode. The core team will help decide whether it should move forward; please wait for that approval instead of opening a feature PR directly.
 
-## Trust & Vouch System
-
-This project uses [vouch](https://github.com/mitchellh/vouch) to manage contributor trust. The vouch list is maintained in [`.github/VOUCHED.td`](.github/VOUCHED.td).
-
-### How it works
-
-- **Vouched users** are explicitly trusted contributors.
-- **Denounced users** are explicitly blocked. Issues and pull requests from denounced users are automatically closed. If you have been denounced, you can request to be unvouched by reaching out to a maintainer on [Discord](https://opencode.ai/discord)
-- **Everyone else** can participate normally — you don't need to be vouched to open issues or PRs.
-
-### For maintainers
-
-Collaborators with write access can manage the vouch list by commenting on any issue:
-
-- `vouch` — vouch for the issue author
-- `vouch @username` — vouch for a specific user
-- `denounce` — denounce the issue author
-- `denounce @username` — denounce a specific user
-- `denounce @username <reason>` — denounce with a reason
-- `unvouch` / `unvouch @username` — remove someone from the list
-
-Changes are committed automatically to `.github/VOUCHED.td`.
-
-### Denouncement policy
-
-Denouncement is reserved for users who repeatedly submit low-quality AI-generated contributions, spam, or otherwise act in bad faith. It is not used for disagreements or honest mistakes.
-
 ## Issue Requirements
 
 All issues **must** use one of our issue templates: