fix: use 'environment' key for MCP env vars in skill example

[definity]

Issue for this PR

Fixes (partially) #35860

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

The built-in skill example uses env for local MCP servers. The schema and runtime expect environment. This causes env vars to silently drop when users or models follow the example provided by OpenCode.

How did you verify your code works?

Tested before/after making this one change. I was working through this using a local model and it even said it followed the skill example verbatim.

1. I copied the skill example verbatim. The skill doc at customize-opencode shows "env": {} as the example and I used that directly, instead of cross-checking against the actual schema at https://opencode.ai/config.json.
2. The skill doc is wrong. That env in the example contradicts the real schema which uses environment. I should have noticed the discrepancy or validated against the authoritative reference before applying anything.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
2. Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Potential Duplicate Found:

• PR fix(skill): correct MCP local server env key to environment in customize-opencode #35867: fix(skill): correct MCP local server env key to environment in customize-opencode
  • fix(skill): correct MCP local server env key to environment in customize-opencode #35867

This PR appears to be addressing the same issue—fixing the MCP environment variable key from env to environment in skill examples. Both PRs are related to issue #35860. You may want to check if PR #35867 has already been merged or is still open, and coordinate with that work to avoid duplication.

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍

[definity]

Perhaps PR #35867 fixes this more completely, but I will leave it to the maintainers to decide!