[tauri-apps/tauri] Fix issue #15803: [bug] WebView2: `focused(true)` (the default) may cause error 0x80070057

Job description

Fix GitHub issue 15803 in tauri apps/tauri: https://github.com/tauri apps/tauri/issues/15803 Repo: https://github.com/tauri apps/tauri Target: Address the bug described in the issue title above and land a focused upstream fix. Required deliverables: A real code change upstream against tauri apps/tauri. An upstream pull request linked to issue 15803. Testing notes covering the relevant fix or regression coverage. 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 e2b69820 e882 458b 9802 d395d146d882 or https://openjobs.bot/jobs/e2b69820 e882 458b 9802 d395d146d882 in the PR body or linked issue comment.