feat(ios): opt-in consumption of sentry-cocoa via Swift Package Manager

Adds a new opt-in path in RNSentry.podspec: when `SENTRY_USE_SPM=1` is set
in the environment before `pod install`, RNSentry pulls `Sentry` from the
sentry-cocoa SPM package (as a binary xcframework) instead of from the
Sentry CocoaPods source build.

Default behavior is unchanged. Existing users on any React Native version
keep their current CocoaPods-based consumption with no action required.

The opt-in path requires React Native >= 0.75 because it uses the
`SPMManager` singleton defined in `react-native/scripts/cocoapods/spm.rb`,
which is loaded transitively from the Podfile via `react_native_pods.rb`.

This is the first step of the broader SPM migration tracked at #5780. It
unblocks experimentation with binary-framework consumption of sentry-cocoa
while keeping CocoaPods as the production default.

Two known caveats for users opting in today:

1. The Sentry xcframework in sentry-cocoa 9.13.0 and earlier is missing the
   `SentrySessionReplayHybridSDK` symbol due to a packaging bug
   (getsentry/sentry-cocoa#7911). Apps that use Session Replay will fail to
   link until that fix ships in a sentry-cocoa release. Apps not using
   Session Replay are unaffected.
2. `SentrySwizzle.h` must be imported via framework-style (`<Sentry/...>`)
   rather than quote-style when the xcframework is the consumption path —
   already handled by #6175 (in this same release).

Verified locally:
- Default `pod install` (no env var) — `** BUILD SUCCEEDED **` on the
  RN sample, identical to the pre-change state.
- `SENTRY_USE_SPM=1 pod install` — Sentry no longer in Podfile.lock,
  `XCRemoteSwiftPackageReference "sentry-cocoa"` injected into the Xcode
  project, [SPM] log lines confirm the helper ran correctly.

Refs: #5780, #6170

Author: alwx

CHANGELOG.md

@@ -10,6 +10,7 @@
 
 ### Features
 
+- Opt-in: consume sentry-cocoa via Swift Package Manager. Set `SENTRY_USE_SPM=1` before `pod install` to pull `Sentry` from sentry-cocoa's SPM package as a binary xcframework instead of the CocoaPods source build. Requires React Native >= 0.75. Default behavior (CocoaPods) is unchanged. ([#TBD](https://github.com/getsentry/sentry-react-native/pull/TBD))
 - Multi-instance `<TimeToInitialDisplay>` / `<TimeToFullDisplay>` coordination ([#6090](https://github.com/getsentry/sentry-react-native/pull/6090))
   - New `ready` prop. When a screen has multiple async data sources, mount one `<TimeToFullDisplay ready={...} />` per source — TTID/TTFD is recorded only when every instance reports `ready === true`.
   - The existing `record` prop is unchanged BUT it is now deprecated in favor of `ready`.

packages/core/RNSentry.podspec

@@ -50,7 +50,29 @@ Pod::Spec.new do |s|
     'DEFINES_MODULE' => 'YES'
   }
 
-  s.dependency 'Sentry', '9.13.0'
+  # Opt-in to consuming sentry-cocoa via Swift Package Manager.
+  # When `SENTRY_USE_SPM=1` is set, RNSentry pulls `Sentry` from the
+  # sentry-cocoa SPM package as a binary xcframework instead of from
+  # the Sentry CocoaPods source build. Defaults to CocoaPods consumption
+  # for backward compatibility with the full RN version range we support.
+  #
+  # Requires React Native >= 0.75 because the SPM helper
+  # (`react-native/scripts/cocoapods/spm.rb`) is loaded transitively from
+  # the Podfile via `react_native_pods.rb`.
+  if ENV['SENTRY_USE_SPM'] == '1'
+    unless defined?(SPM) && SPM.respond_to?(:dependency)
+      raise 'SENTRY_USE_SPM=1 is set but the SPM helper is not loaded. ' \
+            'This requires React Native >= 0.75 and a Podfile that imports ' \
+            'react_native_pods.rb.'
+    end
+    SPM.dependency(s,
+      url: 'https://github.com/getsentry/sentry-cocoa',
+      requirement: { kind: 'exactVersion', version: '9.13.0' },
+      products: ['Sentry']
+    )
+  else
+    s.dependency 'Sentry', '9.13.0'
+  end
 
   if defined? install_modules_dependencies
     # Default React Native dependencies for 0.71 and above (new and legacy architecture)