fix(core): Fix stale deprecation references (#5881)

* fix(core): Fix stale deprecation references

- Update `initialScope` deprecation to point to `getGlobalScope()`/
  `getIsolationScope()` instead of removed `configureScope()` API
- Update stale "Remove in v7" comment to "Remove in v9" since the
  `_experiments` replay options compat shim was not removed in v8

Ref: https://develop.sentry.dev/sdk/

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(core): Show setter pattern in initialScope deprecation message

The deprecation should show how to mutate the scope, not just how to
get it.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: antonis

packages/core/src/js/integrations/default.ts

@@ -148,7 +148,7 @@ export function getDefaultIntegrations(options: ReactNativeClientOptions): Integ
     (options._experiments && typeof options._experiments.replaysSessionSampleRate === 'number');
 
   if (!hasReplayOptions && hasExperimentsReplayOptions) {
-    // Remove in the next major version (v7)
+    // Remove in the next major version (v9)
     options.replaysOnErrorSampleRate = options._experiments?.replaysOnErrorSampleRate;
     options.replaysSessionSampleRate = options._experiments?.replaysSessionSampleRate;
   }

packages/core/src/js/options.ts

@@ -125,7 +125,7 @@ export interface BaseReactNativeOptions {
 
   /**
    * Set data to the inital scope
-   * @deprecated Use `Sentry.configureScope(...)`
+   * @deprecated Use `Sentry.getGlobalScope().setTag(...)`, `Sentry.getGlobalScope().setUser(...)`, etc. instead.
    */
   initialScope?: CaptureContext;