Fix for #7229 Fix/project sidebar folder name

[0xajka]

Fix for #7229 : Project sidebar displays full paths instead of folder names on Windows

Problem:

On Windows, the sidebar showed full paths like C:\Users{name}...\project-name instead of just project-name
The tooltip on hover also displayed the full path
Root cause:

getFilename() utility only split by /, not handling Windows \ separator
Tooltip directly used worktree instead of extracting the folder name
Duplicate getFilename function in dialog-edit-project.tsx
Changes:

Updated getFilename() in packages/util/src/path.ts to split by both / and
Changed tooltip in packages/app/src/pages/layout.tsx to show folder name
Removed duplicate function, using imported utility in packages/app/src/components/dialog-edit-project.tsx

Before:

After:

Note: this is a redo of #7230 as I messed up and included commits from an unmerged PR in it and so closed and redid it here

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

No duplicate PRs found

(Note: PR #7230 was mentioned in the description as the previous attempt that was closed, but it doesn't appear in search results, which is expected if it was already closed/replaced by the current PR #7232. PR #6082 is related to Windows path handling but addresses a different scope - Git Bash/MSYS paths rather than sidebar folder name display.)

[adamdotdevin]

@0xajka just making sure, you tested on non-Windows as well?

[0xajka]

No I don't have a non windows machine, sorry I didn't think about that, if needed I can use a live boot of linux and try it

[0xajka]

@adamdotdevin re: testing on a non windows machine, I was unable to get my computer to boot linux, did test the getFileName function manually to ensure it would work for either windows (which I also built the app and tested that way) and linux style (tested manually that the function would work

)

Also the forced push was I noticed there was still a reference to a function from my other PR that wasn't merged so I removed it