What this PR does / why we need it:

Added a new PodAnnotations map[string]string field to the FeatureStoreServices struct, allowing users to declaratively set annotations on the Deployment's pod template. Users can now enable OpenTelemetry auto-instrumentation (or any annotation-driven integration) like this:

apiVersion: feast.dev/v1
kind: FeatureStore
metadata:
  name: my-feast
spec:
  services:
    podAnnotations:
      instrumentation.opentelemetry.io/inject-python: "true"
    onlineStore:
      server:
        metrics: true

Which issue(s) this PR fixes:

Fixes #6194

Checks

• I've made sure the tests are passing.
• My commits are signed off (git commit -s)
• My PR title follows conventional commits format

Testing Strategy

• Unit tests
• Integration tests
• Manual tests
• Testing is not required for this change