Allow opening file paths relative to terminal's cwd


https://github.com/zed-industries/zed/assets/67913738/413a1107-541e-4c25-ae7c-cbe45469d452


Release Notes:

- Added support for opening file paths relative to terminal's cwd
([#7144](https://github.com/zed-industries/zed/issues/7144)).

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Co-authored-by: Kirill <kirill@zed.dev>