feat: MAUI trace log correlation

[abelonogov-ld]

Summary

• Introduce ObservabilityService — a new internal service class that consolidates all native bridge calls (logging, errors, metrics, tracing) and owns the LDTracer lifecycle. Replaces the deleted NativeObserve class and eliminates scattered #if IOS / ANDROID directives from LDObserve.
• Add trace-log correlation — RecordLog now accepts an optional SpanContext parameter, forwarding traceId/spanId to the native logger. Falls back to the ambient Activity.Current when no explicit context is provided.
• Expose RealLogger on Android and ObjcLogger on iOS — new native wrappers obtained via LDObserveBridgeAdapter.getLogger() / LDObserveBridge.getObjcLogger(), replacing the old recordLog method on ObservabilityBridge.
• Rename NativeSessionReplay → SessionReplayService and NativeObserve → ObservabilityService throughout the plugin layer for consistent naming.
• Make LDTracer non-singleton — constructor now takes serviceName, created and owned by ObservabilityService during initialization.
• Simplify LDObserve static facade — all methods delegate to ObservabilityService via a volatile reference; safe no-op behavior before initialization. Add StartRootSpan, RecordError(Exception) overload.
• Extract option classes — LDObservabilityOptions, LDPrivacyOptions, LDSessionReplayOptions moved from ObservabilityBridge.kt into a dedicated OptionsBridge.kt.
• Update sample app — add "Log with Context" button demonstrating span-context-attached logging; use RecordError(Exception) overload; route span creation through LDObserve.StartRootSpan.

Test plan

• Build Android and iOS targets to verify native bindings compile (RealLogger, ObjcLogger)
• Run sample app on Android emulator — tap "Trigger Log", "Log with Context", "Trigger Error", "Sequential Spans", "Custom Span" and verify data reaches the backend
• Run sample app on iOS simulator — same smoke test
• Verify logs sent via "Log with Context" carry the expected traceId/spanId in the backend
• Confirm LDObserve methods are no-ops before plugin registration (no crashes)
• Check that RecordError(Exception) sends both message and full stack trace

---

Note

Medium Risk
Medium risk due to refactoring the observability facade and plugin initialization flow, plus new native bindings (ObjcLogger/RealLogger) that must compile and behave consistently on both iOS and Android.

Overview
Adds trace-log correlation and centralizes native observability calls. Introduces an internal ObservabilityService that owns LDTracer lifecycle and routes logs/errors/metrics/spans through platform-native bridges, replacing the deleted NativeObserve and removing per-call #if IOS/ANDROID branching from LDObserve.

LDObserve.RecordLog now accepts an optional OpenTelemetry SpanContext (falling back to Activity.Current) and forwards traceId/spanId to a new native logger interface; iOS binding adds ObjcLogger/getObjcLogger, Android adds RealLogger/getLogger and moves Kotlin option DTOs into OptionsBridge.kt.

Plugin wiring is updated to use ObservabilityService/SessionReplayService (renamed from NativeSessionReplay), with PluginOrchestrator initializing LDNative and then calling LDObserve.Initialize when observability is enabled. Sample app is updated to demonstrate "Log with Context", RecordError(Exception), and StartRootSpan usage.

^{Reviewed by Cursor Bugbot for commit d798511. Bugbot is set up for automated code reviews on this repo. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, have a team admin enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit c39ec78. Configure here.}