[abelonogov-ld]

Summary

Adds a global attributes API to the Android observability SDK. This is one of a set of matching PRs across SDKs that share the same semantics (see #858, #859, #861, #856, #863, launchdarkly/swift-launchdarkly-observability#290).

• LDObserve.setAttributes(Attributes) and LDObserve.setAttributes(Map<String, Any?>) merge attributes by key into one in-memory, process-wide map; LDObserve.removeAttributes(Collection<String>) removes keys.
• Applied to every span (values captured at span start), every log record (including crash reports) and every metric data point recorded after the call, including the launch-time histogram.
• Precedence: per-call attributes > globals > resource. Globals only fill missing keys and never overwrite. Upstream OtelRumConfig.setGlobalAttributes is intentionally not used, because its appenders overwrite per-call values. Instead, internal span and log processors are registered ahead of the SDK's sampling and export processors, and metric record methods merge globals under per-call values.
• session.id and highlight.session_id are ignored (a warning is logged).
• Not persisted and not cleared on session rotation. Calls made before the SDK initializes take effect, because the store exists independently of the SDK instance.
• Reads are a lock-free load of an immutable snapshot; writes rebuild it under a lock.
• README documents the API with a Kotlin example.

How did you test this change?

• New JVM unit tests (GlobalAttributesStoreTest, GlobalAttributesPipelineTest): merge/remove, re-setting a key with a different value type, reserved keys, per-call precedence, concurrent writers, set-before-init through LDObserve, globals captured at span start, and globals reaching exported spans, logs and metric data points through real OpenTelemetry providers wired like the SDK.
• ./gradlew :lib:compileDebugKotlin :lib:test passes (559 tests, debug and release).

Are there any deployment considerations?

• ObservabilityOptions is unchanged. The only API change is three new methods on Observe (inherited by LDObserve and its companion), with default implementations, so Kotlin implementers need no changes.
• Java and MAUI callers use LDObserve.Companion.setAttributes(...) / removeAttributes(...), like the other LDObserve methods. feat(maui): add SetAttributes and RemoveAttributes #863 (MAUI) is stacked on this PR.
• Global attributes are added to metric data points, so they increase metric cardinality.

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Note

Overview
Adds process-wide global attributes on the Android observability SDK via LDObserve.setAttributes (OTel Attributes or plain map) and LDObserve.removeAttributes.

Globals are stored in a singleton GlobalAttributesStore so calls before SDK init still apply once the pipeline starts. They are merged into spans (snapshot at span start), logs (via new processors registered ahead of sampling/export), and metrics (including launch-time histograms), with per-call attributes winning over globals and reserved session keys ignored with a warning. README and the compose e2e app document/repro UTM-style globals and precedence.

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