chore: update docs for ui_locales param in sso callback url

[vtsl-DevRev]

Summary

Adds support for a ui_locales query param on the SSO callback URL so the portal can be rendered in a specific language for the incoming session. The param accepts a BCP-47 locale tag (e.g., en-US, fr-FR, ja-JP) and works alongside the existing redirect_to param — e.g. …/callback/sso?jwt=&redirect_to=/article/ART-1&ui_locales=ja-JP.

The locale only takes effect if it has been added under Settings → Language and Region → Portal Supported Languages and then published from Portal Settings. Unsupported or unpublished tags are ignored and the portal falls back to its default locale, so existing SSO flows are unaffected. The SSO setup doc is updated with the new param and prerequisites.

Connected Issues

• Work Item :- https://app.devrev.ai/devrev/issue/PORT-27

Craftsmanship, Integrity, and Devil’s Advocacy

• Testing: Negative test cases: null or default values, crash and fault injection tests
• Testing: Boundary conditions: rolling upgrades, denial-of-service, etc.
• Testing: Fixing a few existing — flaky or permanently-broken — test cases
• Observing: Detailed error codes so machines can understand
• Observing: Adding superior metrics for future debugging
• Observing: Tracing the hairiest pathways for field serviceability
• Training: KnowledgeOps update? So AI always works.