feat: added the create function to the fs module

[hankertrix]

It is mostly based on the create_do function.

Closes #1709.

[sxyazi]

Sorry, I'm afraid I can't accept this PR because the current implementation is too specific to a single feature and lacks broader usability.

Creating files/directories is a bit complex and requires some design at the API level. I haven't had the time to dive into it yet, but I do have some rough ideas:

• For directory creation, the default behavior should be non-recursive, with an option for recursive creation.
• There shouldn't be a dedicated API for creating files. Instead, files should be opened, returning a handle that can be used for chained operations like writing, flushing, etc.
• When opening a file, it should be possible to specify the mode (read/write, append, truncate, etc.). Rust's OpenOptions is a good reference: https://doc.rust-lang.org/std/fs/struct.OpenOptions.html.
• The file handle should interoperate with other APIs, such as opening a process via the Command API and redirecting the process's stdout to the file handle — we can tackle this part later.

Would you like to give this a try in this PR? I can provide some guidance if needed. Or feel free to close this PR, and I'll try to implement it after the 0.4 release, once I get some time.

[hankertrix]

Ah I see, no worries. I can try to tackle the first 3 points you mentioned, but it'll take me a lot more time, which I currently don't have much of until about 2 months later.

I'll convert this pull request to a draft.

[hankertrix]

Closing this pull request for now, I’ll create another pull request when I implement the API.

The reason is to not pollute the branch with merge commits.