feat: AnalyticsClient wiring + openURL public API [rn] (3/4)

[choudlet]

Summary

Slice 3 of 4 in the RN lifecycle stack (sc-36800). Wires the storage foundation (#34) and emitter (#35) into `MetaRouterAnalyticsClient`, adds the public `openURL` API, and flips the `trackLifecycleEvents` default to opt-in.

Stacked on #35. Review the diff against that branch.

Behavior contract

• Cold-launch state machine — detects fresh install vs SDK-upgrade vs version change vs no-op. Installed/Updated emits before the first `Application Opened` so attribution pipelines see install/update before session start.
• Background-launched processes (push, headless JS) suppress the cold-launch Opened; the next `background → active` emits with `from_background: false` as the cold-launch bridge.
• `inactive → active` (Control Center, FaceID, system alerts) is suppressed — only `background → active` emits Opened.
• `Application Backgrounded` is enqueued before the flush-to-disk pass so the event ships in the same drain.
• Deep links auto-captured via `Linking.getInitialURL()` (cold launch) and `Linking.addEventListener('url', ...)` (runtime). One-shot buffer with last-write-wins overwrite, cleared on next Opened emit.

Public API

```ts
analytics.openURL(url: string, sourceApplication?: string): void
```

Forwards a URL the host received from any source (Linking, UIScene URL handler, Android Intent, deep-link libraries that bypass Linking) so it's attached to the next `Application Opened`. No-op with a `Logger.warn` when `trackLifecycleEvents` is disabled — silent no-ops are bad DX. Wired through:

• `AnalyticsInterface` (public type)
• `proxyClient` (so pre-bind calls are queued and replayed on bind)
• `init.ts` `boundClient`

Defaults flipped

`InitOptions.trackLifecycleEvents` now defaults to `false` (opt-in). Existing customers upgrading the SDK do not begin emitting these events without explicitly setting the flag. Matches iOS / Android v1.5.

App metadata consolidation

A single `appContext` snapshot is held on the client, populated once from `this.context.app` after `getContextInfo` resolves. Replaces three sites that independently re-derived `{version, build}` from the cached context — parity with the iOS `AppContext` consolidation. New `versionInfo()` private helper centralizes the read.

Test changes

• New `disableDispatcherFlush` helper in the lifecycle `describe` block. Why: the dispatcher's `flush()` synchronously drains the in-memory queue inside its first `while` iteration (`drainBatch` runs before the `await`), which empties events emitted right before `this.flush()` in `handleAppStateChange`. Production behavior is correct (event ships via fetch); the helper keeps the queue snapshot intact for assertions.
• 6 new `openURL` tests — buffered URL on next Opened, `sourceApplication` → `referring_application`, last-write-wins, one-shot clear, disabled no-op + warning, invalid input rejection.
• 1 new test asserts the opt-in default (omitted flag → no events).
• Pre-existing `preserves lifecycle storage across reset()` fixed — the AsyncStorage mock module shape is `{ default: { ... } }`, so the spy must target the `default` export.

Stack

1. #34 — storage foundation
2. #35 — emitter
3. This PR — client wiring + `openURL` + opt-in default
4. README documentation

Test plan

• `npx jest src/analytics/MetaRouterAnalyticsClient.test.ts` — 87 tests pass
• `npx jest src/analytics/proxy/proxyClient.test.ts` — passes
• `npx tsc --noEmit` clean