Fix undefined errors in metrics reports

[daniyelnnr]

What is the purpose of this pull request?

This PR prevents undefined errors during status tracking and metrics reporting.

What problem is this solving?

Addresses a bug related to metrics tracking by ensuring that the global.metrics object is properly initialized in both master and worker processes. This is done by ensuring that it is initialized in both master and worker processes by moving its initialization into the shared startApp function in src/service/index.ts, and removing redundant initialization and type declarations from src/service/worker/index.ts.

How should this be manually tested?

One can release a version of service-runtime-node using this changes and make it available on a test cluster. Then start a store with this infrastructure and observe its pods running without CrashLoopBackOff due to Cannot read properties of undefined errors.

Screenshots or example usage

Types of changes

• Bug fix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Requires change to documentation, which has been updated accordingly.