Do not fail to write entry into malformed SQLite database

[abyss7]

In case of free space shortage or any other reason the SQLite file may become malformed. We need to properly handle this situation:

• try to repair,
• drop broken image and recreate it,
• try to write new entry again.

Otherwise, the daemon asserts here: https://github.com/abyss7/dist-clang/blob/master/src/cache/file_cache.cc#L100