refactor: near-identical cleanup and StatefulSet functions should be deduplicated

[digiserg]

Summary

cleanupInternalSearchResources and cleanupInternalTimeseriesResources differ only in component name. Similarly, ensureSearchStatefulSet and ensureTimeseriesStatefulSet are 180+ lines each with near-identical structure. This duplication increases maintenance burden and risk of divergence — a fix applied to one but not the other creates subtle bugs.

Detailed Requirements

Extract common helper functions:

• cleanupInternalComponentResources(ctx, server, componentName) — replaces both cleanup functions
• buildStatefulSetSpec(componentName, config) or similar — replaces both ensure functions

Component-specific configuration (ports, paths, environment variables) should be passed as parameters or a config struct.

Location

• internal/controller/axonopsserver_controller.go:1043-1157 (cleanup functions)
• internal/controller/axonopsserver_controller.go:1548-1747 (ensureSearchStatefulSet)
• internal/controller/axonopsserver_controller.go:1862-2117 (ensureTimeseriesStatefulSet)

Acceptance Criteria

1. Single cleanupInternalComponentResources function replaces both cleanup functions
2. Common StatefulSet builder replaces both ensure functions
3. Component-specific config (ports, paths, env vars, image) passed as parameters or config struct
4. All existing tests pass without behavioral changes
5. Diff shows net reduction in lines of code

Testing Requirements

• All existing unit tests pass unchanged
• New unit tests for the extracted helper functions with different component configs
• Verify both Search and TimeSeries StatefulSets are functionally identical to before

Documentation Requirements

• Add godoc to the new helper functions explaining the parameterization

Dependencies

• Should be done after refactor: Reconcile method has excessive cyclomatic complexity (~40+) #39 (Reconcile complexity reduction) for cleaner implementation