fix: repair broken unit tests

[sayanget]

Problem Summary

Several unit tests in the swap crate are failing due to outdated mocks, database connection issues, or environment mismatches.

Solution Approach

• Identified failing tests in database::sqlite.
• Updated mock structures to align with current protocol requirements.
• Ensured temporary database files are correctly handled during concurrent test runs.

Test Evidence

Verified that database::sqlite::tests::test_insert_and_load_monero_address_pool and related tests pass locally using cargo test.

[Einliterflasche]

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