fix sqlite locking during index clearing

[uinstinct]

Description

When doing a force reindex, sqlite gets locked and the associated sqlite file does not get deleted as expected.

Added corresponding fix and tests to ensure this case is handled.

reference: https://discord.com/channels/1108621136150929458/1364504237677088809/1364504237677088809

Checklist

• [] I've read the contributing guide
• [] The relevant docs, if any, have been updated or created
• [] The relevant tests, if any, have been updated or created

Screenshots

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Testing instructions

[ For new or modified features, provide step-by-step testing instructions to validate the intended behavior of the change, including any relevant tests to run. ]