feat(ui): add project filter/sort support

[userquin]

Description

Adding support to filter tests by project and allow sort tests by project (rn sorted by filename + project name).

supersedes #8688

NOTE: running pnpm vitest --ui from test/core using Node 24.8.0 Vitest stops working on my Windows laptop (from time to time), the process just finish without any error/feedback in the terminal, and the WebStorm terminal broken ctrl + C or arrow up/down not working:

some screenshots

test/core without projects

new filter by project and sort projects in the UI

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[userquin]

✔️ done: I need to review the numbers at explorer header when filtering by project, looks like using global data instead filtered.