Add node count badge to project cards on dashboard

[kimgh06]

The dashboard project cards only show the project name. It would be helpful to show the node count.

Suggested approach:

• The /api/teams/:slug/projects response already includes project data
• Add a small badge showing node count on each project card
• Consider using the summary endpoint or adding a count field

Files to modify:

• frontend/src/routes/dashboard/[teamSlug]/+page.svelte

Difficulty: Beginner