Introduce ipfs files write --nocopy or equivalent

[Winterhuman]

Checklist

• My issue is specific & actionable.
• I am not suggesting a protocol enhancement.
• I have searched on the issue tracker for my issue.

Description

Currently, if you want to add files to IPFS and to the MFS, but without duplicating data by creating the files in the database, you need to do ipfs add --nocopy and ipfs files write afterwards.

Instead, I propose a ipfs files write --nocopy (or similar single command, whatever makes the most sense) to simplify adding a file to the MFS without duplicating files in the database. This idea was sparked from a conversation on Matrix where someone wanted to add a large amount of files to the MFS without duplicating them.

Although it's currently possible to achieve this by combining the add and files write commands into one, it's not ideal.

Note, #8504 means that ipfs files write itself could be replaced with ipfs files add in future. In which case, I propose --nocopy should be an option for that command if it's not already been considered.

[Winterhuman]

Now thinking about it, #8504 states that it plans to transfer most of ipfs add's options over including --nocopy, so this issue won't be relevant when ipfs files write is replaced. I'll close the issue.