[FIXED] Filestore with encryption may erroneously reset meta.key

[MauriceVanVeen]

If a server was hard killed and was not able to write the index.db file, or it was corrupted, it would allow the stream to be loaded but without initializing the keys used for encrypting the meta.inf and index.db files. The next graceful shutdown would generate the index.db file, but in so doing would regenerate the meta.key as well. On startup the stream would not be able to load since the meta.key was new, but the meta.inf was still encrypted with the old key.

This PR proposes to simply always recover the keys if the key file exists, and not rely on the index.db recovery path.

Signed-off-by: Maurice van Veen github@mauricevanveen.com

[neilalexander]

LGTM