Expose additional native SDK options relevant to React Native (ANR, app-hang/app-start, breadcrumb toggles)

[antonis]

Problem Statement

Several options in the underlying sentry-cocoa and sentry-java SDKs are not forwarded to React Native users, even though they cover native-only signals the JS layer can't observe (ANRs, app hangs, app-start, view hierarchy, native breadcrumbs). Because in RN most HTTP/errors/tracing live in JS, only the genuinely native-relevant options are proposed here.

Forwarding paths for reference: iOS relies on cocoa's dictionary parser (SentryOptionsInternal) plus explicit keys in RNSentryStart.m; Android maps every key by hand in RNSentryStart.java.

All options below already exist in the currently bundled native SDKs (cocoa 9.29.0, sentry-java 8.57.0).

Proposed — high value for RN

RN option	Platform	Native key	Since (native)	Native docs	Why it matters for RN
anrTimeoutIntervalMillis	Android	setAnrTimeoutIntervalMillis	sentry-java 2.1.0	app-not-responding	ANRs fire on the Android main/UI thread every RN app has; JS can't tune this. iOS already exposes appHangTimeoutInterval — parity gap.
enableAnrTracking	Android	setAnrEnabled	sentry-java 2.0.0	app-not-responding	Master ANR toggle; today only killable by disabling all crash handling.
reportHistoricalAnrs	Android	setReportHistoricalAnrs	sentry-java 6.24.0	app-not-responding	Report ANRs from prior runs; parallels the already-exposed enableHistoricalTombstoneReporting.
enableReportNonFullyBlockingAppHangs	iOS	enableReportNonFullyBlockingAppHangs	cocoa 8.39.0	app-hangs	Pairs with the exposed enableAppHangTracking; app hangs are a native UI-thread signal invisible to JS.
enablePreWarmedAppStartTracing	iOS	enablePreWarmedAppStartTracing	cocoa 8.0.0	options#enablePreWarmedAppStartTracing	Pairs with exposed enableAppStartTracking; pre-warm skew corrupts a headline mobile metric only native can measure.
reportAccessibilityIdentifier	iOS	reportAccessibilityIdentifier	cocoa 8.32.0	options#reportAccessibilityIdentifier	PII knob for the exposed attachViewHierarchy. Must be gated on sendDefaultPii.

Proposed — noise-reduction batch (expose primarily as opt-out)

Native HTTP breadcrumbs largely duplicate what the JS SDK already records, so the value is the off-switch, not the feature.

RN option	Platform	Native key	Since (native)	Native docs
enableNetworkBreadcrumbs	iOS	enableNetworkBreadcrumbs	cocoa 7.6.0	options#enableNetworkBreadcrumbs
enableAutoBreadcrumbTracking	iOS	enableAutoBreadcrumbTracking	cocoa 7.21.0	options#enableAutoBreadcrumbTracking
enableActivityLifecycleBreadcrumbs	Android	setEnableActivityLifecycleBreadcrumbs	sentry-java 2.1.0	breadcrumbs
enableAppLifecycleBreadcrumbs	Android	setEnableAppLifecycleBreadcrumbs	sentry-java 2.1.0	breadcrumbs
enableSystemEventBreadcrumbs	Android	setEnableSystemEventBreadcrumbs	sentry-java 2.1.0	breadcrumbs
enableAppComponentBreadcrumbs	Android	setEnableAppComponentBreadcrumbs	sentry-java 2.1.0	breadcrumbs
enableNetworkEventBreadcrumbs	Android	setEnableNetworkEventBreadcrumbs	sentry-java 6.17.0	(not documented upstream)
enableMetricKitRawPayload	iOS	enableMetricKitRawPayload	cocoa 8.29.0	options#enableMetricKitRawPayload

Out of scope (low value for RN)

• propagateTraceparent — traceparent propagation only matters for requests the native layer originates, which is rare in RN (fetch/XHR + propagation are handled in JS).
• attachAllThreads — only adds value on native crashes (the minority in RN) and is currently non-functional; needs a separate cleanup decision.

Notes

• Each new option must work on both architectures (New + Old) and be gated appropriately (e.g. reportAccessibilityIdentifier on sendDefaultPii).
• The iOS options above are already read by cocoa's dict parser, so most need only a type + JSDoc; the Android options each need a mapping line in RNSentryStart.java.
• Related bug (tracked separately): shutdownTimeout is silently ignored on iOS.

[linear-code]

RN-786