Log file name collision

Sometimes the log filename collides and results in an exception.
1. When there are no valid gps-time and 1980-01-01 is used.
2. When the minute is the same over two log files (it can happen if extensive logging is used).

One solution could be to add seconds to the naming, and add a sequence no at the end if there is a collision.

Locate the code that generates log filenames and inspect how invalid GPS time and minute-level timestamps are handled. Reproduce both collision cases described in the issue, then verify that repeated or invalid-time logs receive unique filenames without exceptions.

Written by the indexing model from the issue text.