fix(ui): prevent AppCard crash on missing ingress and improve metrics display

[Buddruggy]

Description

Fixes a frontend crash on the pipeline apps page when an app CR is missing addons and/or ingress.hosts, and improves AppCard metrics rendering for apps that include addon pods.

Motivation / context

• Pipeline page can white-screen with: TypeError: Cannot read properties of undefined (reading 'length')
• Root cause: AppCard assumes app.addons and app.ingress.hosts always exist, but apps returned from CRDs may omit them.
• Additionally, when one addon pod has resource percentages and the app pod does not, the card switches to empty progress bars instead of showing usable CPU/memory usage values.

Fixes #

Type of change

• Bug fix (non-breaking change which fixes an issue)
• Template (non-breaking change which adds a template)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• I've built the image and tested it on a Kubernetes cluster

Test Configuration:

• Operator Version: existing cluster install
• Kubernetes Version: TKE (in-cluster)
• Kubero CLI Version (if applicable): v2.4.x

Steps:

1. Open a pipeline containing an app without ingress.hosts (or with ingress.enabled: false) → page no longer crashes.
2. Open an app with an addon pod that has resource requests while the app pod does not → card shows a metrics table instead of empty bars.
3. Open apps where every pod has percentages → progress bars still work.
4. Open app detail for an app without hosts → no crash on metrics / open actions.

Checklist:

• I removed unnecessary debug logs
• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I documented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings