fix(console): follow-up to #13108 — /docs/en still 404 and English locale does not persist #13606

Description

This is a follow-up to #13108.

I originally reported this issue in #13108, and a fix was merged, but the problem is still reproducible in production.

So I am opening this issue to track the remaining behavior that was not resolved.

This issue is not limited to Korean.
If oc_locale is set to any non-English locale (for example: ko, ja, fr, etc.), selecting English from the language selector may not stay in English.

Also, /docs/en still returns 404 in production.

Expected behavior

• /docs/en should resolve to English docs consistently (or redirect to canonical English docs path, e.g. /docs).
• Selecting English should persist English and should not revert to a previous non-English locale.
• /docs/en/* paths should also resolve consistently for English docs.

Actual behavior

• /docs/en returns 404 in production.
• English selection can be overridden by existing non-English locale state (oc_locale).
• In practice, English does not remain sticky in some docs navigation flows.

Reproduction (production)

1. Set oc_locale to a non-English locale (e.g. ko).
2. Open https://opencode.ai/docs.
3. Try either:
   • Directly navigate to https://opencode.ai/docs/en, or
   • Select English from the language selector in docs.
4. Observe current behavior.
   Observed result

• /docs/en returns 404.
• English selection may fall back to the previous non-English locale.

Notes
Likely related to docs path canonicalization for /docs/en* and locale cookie synchronization in docs proxy routing.

Plugins

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OpenCode version

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Steps to reproduce

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Screenshot and/or share link

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Operating System

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Terminal

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