* feat: add `created_at` and `updated_at` to wallets and accounts
the title says it all :)
* fixup!
* nitpicks :)
* fixup!
* sqlite fix
* sqlite compat
* fixup!
* mypy
* revert db py
* motorinas suggestions
* int(time()) proper default values in migration
* uncomment migration
* use now = int(time()) idiom to make code more readable
also this fixes the issue where time() is called multiple times
providing different return values for multiple invocations
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Co-authored-by: Pavol Rusnak <pavol@rusnak.io>