Auto focus text field when creating new files and folders

[FastestMolasses]

Description

When we create a new file or folder, CodeEdit will now automatically focus the renaming field so the user can directly set the file name in one step.

Files and folders are no longer created immediately, instead a "phantom" file will be represented in the project navigator, and will only actually create the file when the user sets a valid file name.

Lastly, we do not automatically set the file extension for the user.

Related Issues

Checklist

• I read and understood the contributing guide as well as the code of conduct
• The issues this PR addresses are related to each other
• My changes generate no new warnings
• My code builds and runs on my machine
• My changes are all related to the related issue above
• I documented my code

Screenshots

auto.rename.mov

[thecoolwinter]

This looks great, just needs the lint fix and we can merge!

[FastestMolasses]

@thecoolwinter Looks like just an unrelated issue with the CEActiveTaskTests test

[thecoolwinter]

I agree, I can't seem to track down why those tests are failing but they appear to be fixed on main. We can merge without those passing tests.

[thecoolwinter]

Found one bug. If there's a file system event while the new file item is focused, it silently fails to create the file.

Screen.Recording.2025-08-08.at.10.07.30.AM.mov