Re-enable files/write

[TheDiscordian]

Currently we do ipfs add then ipfs cp. Let's switch this to two options, either bulk ipfs add (#31) or ipfs files write. Not entirely sure which will be more performant.

This feature was removed in 086b613

However with ipfs/kubo#7916 being fixed, now it should be usable again (fingers crossed).

[TheDiscordian]

This issue can be closed after files/write is implemented, the switch can come in after #31 is complete (which isn't on the v1.0.0 milestone rn).

[TheDiscordian]

Actually not sure how important this is, so going to move it to the back-burner.

[TheDiscordian]

Instead of a switch, bulk add on init using #31, then add subsequent files / update using files/write.