Prepare 0.6.35 changelog

[EKKOLearnAI]

Summary

• bump the Web UI, desktop, lockfile, and OpenAPI versions to 0.6.35
• add the 0.6.35 changelog in all 10 supported locales
• highlight production enablement of Ekko Agent persistent memory, its 4,000-token recall budget, improved relevance search, and safer model request handling
• update the website's supported Web UI version list

Why

Prepare the next patch release after enabling the Ekko Agent memory system in production through #2246.

User impact

Users will see the new 0.6.35 release notes and receive the production-ready persistent memory behavior introduced in #2246.

Validation

• npm run harness:check
• npm run build