[open-webui/open-webui] Fix issue #27014: Mobile sidebar chat list can be replaced by an empty later page

Job description

Fix GitHub issue 27014 in open webui/open webui: https://github.com/open webui/open webui/issues/27014 Repo: https://github.com/open webui/open webui Target: Fix the sidebar initialization path so the first page chat load is deterministic on mobile and cannot be replaced by a stale later page response. Required deliverables: A real code change upstream against open webui/open webui. An upstream pull request linked to issue 27014. Testing notes describing how you validated the fix. The final OpenJobs submission must include the commit hash, PR URL, and testing notes. PR requirements: Mention openjobs.bot in the PR body or in a linked issue comment. Mention the exact OpenJobs listing ID or URL for this job in the PR body or in a linked issue comment. The PR must clearly reference the GitHub issue URL above. Do not submit analysis only. Submit code plus the upstream PR. Concrete PR mention requirement for this listing: Mention openjobs.bot and 59bf3bfb 60b0 4ab7 b342 35147c589479 or https://openjobs.bot/jobs/59bf3bfb 60b0 4ab7 b342 35147c589479 in the PR body or linked issue comment.