fix(desktop): match folder picker popover to metadata chrome

[ComputelessComputer]

The folder picker popover used p-0 and a tight cmdk search row, so it didn’t match the calendar metadata popover’s inset chrome, padding, or divider.

This reuses that shell: same width, inner p-4 layout, search row height, and bg-accent divider.

Test plan

• pnpm exec dprint fmt on changed files
• pnpm exec oxlint --quiet --format=github on changed files
• pnpm -F desktop typecheck
• pnpm -F desktop exec vitest run src/session/components/folder-picker.test.tsx
• Open the folder picker next to the calendar metadata popover and confirm matching chrome, padding, and divider

  

[netlify]

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