enhancement(core): add config resolve and doctor commands

[LeonardBode]

Problem

OpenCode config can be composed from multiple sources, but there is no first-class CLI flow that shows the fully resolved runtime config or explains why a value won, was ignored, or is still unresolved. Downstream integrations end up building custom sync and debugging layers around config merge behavior.

Impact

This makes enterprise and generated-config setups harder to operate, especially when users mix global, project, inline, and generated config. It also turns troubleshooting into trial-and-error because there is no single source of truth for the effective config.

Fix

Add opencode config resolve and opencode config doctor.

• resolve should print the effective merged config in a machine-readable form.
• doctor should report source precedence, unknown keys, deprecated keys, unresolved {env:...} and {file:...} refs, and ignored sections.
• Both commands should work with custom config paths and eventually support selected profiles once profiles land.

File

docs/config/ L1

[github-actions]

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What needs to be fixed:

• Feature requests must use the [FEATURE]: prefix in the title (e.g. [FEATURE]: add config resolve and doctor commands)
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• The issue appears to be AI-generated (highly structured sections, formal language, and a ## File field with placeholder content docs/config/ L1). AI-generated walls of text are not acceptable per our guidelines — please rewrite this in your own words describing what you actually need

Please edit this issue to address the above within 2 hours, or it will be automatically closed.

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This issue might be a duplicate of existing issues. Please check:

• [FEATURE]: Config debugging tool #7071: Config debugging tool — very similar request for a tool to help debug/inspect config loading and behavior

If you believe this was flagged incorrectly, please let a maintainer know.

[github-actions]

This issue has been automatically closed because it was not updated to meet our contributing guidelines within the 2-hour window.

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