fix(setting): handle delete of setting item with empty key

[j2rong4cn]

Motivation and Context / 背景

Close #2127

How Has This Been Tested? / 测试

Checklist / 检查清单

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  • OpenList-Frontend #XXXX
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[Copilot]

Pull request overview

This PR fixes a bug where deleting a setting item caused a "UNIQUE constraint failed" error (issue #2127), which resulted in a 502 response and prevented the server from restarting. The fix addresses both the immediate delete issue and adds preventive cleanup for corrupted data.

Changes:

• Modified the DeleteSettingItemByKey function to use an explicit WHERE clause instead of relying on GORM's implicit primary key handling
• Added cleanup logic during bootstrap to detect and remove setting items with empty keys

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
internal/db/settingitem.go	Changed delete implementation to use explicit WHERE clause with columnName() helper, making it consistent with other database operations in the file
internal/bootstrap/data/setting.go	Added check to detect and clean up corrupted setting items with empty keys during initialization, preventing them from causing issues later

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