fix(insights): gracefully handle no manifests and missing symbols

[intellix]

Overview

Closes #6012

When fetching insights, it throws a 500 error each time for my projects when there are no manifests

What is it?

• Feature / enhancement
• Bug
• Docs / tests / types / typos

Description

. After pulling it locally and running it on a brand new app, I've noticed there were 2x errors:

• Cannot use inArray without at least 1 item (so I've added a condition to not use it when it's empty)
• Cannot read name of undefined:

[vite] Internal server error: Cannot read properties of undefined (reading 'name')
  File: /Projects/qwik/packages/insights/src/stats/edges.ts:211:4
  209|    clusters.forEach((cluster) => {
  210|      const symbols = cluster.map((id) => symbolVectors.symbols[id]);
  211|      const symbolNames = symbols.map((s) => s.name);

Use cases and why

• 1. One use case
• 2. Another use case

Checklist:

• My code follows the developer guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• Added new tests to cover the fix / functionality

[netlify]

👷 Deploy request for qwik-insights pending review.

Visit the deploys page to approve it

Name	Link
🔨 Latest commit	ab7f37e

[wmertens]

LGTM