fix(ios): address Cursor Bugbot review findings on PR invertase#8933

- analytics: include FirebaseAnalytics/IdentitySupport when
  $RNFirebaseDisableSPM forces CocoaPods on RN >= 0.75. The previous
  `unless defined?(spm_dependency)` guard skipped the IdentitySupport
  block even when the user explicitly opted out of SPM.

- installations: remove redundant `#import "FirebaseInstallations/
  FIRInstallations.h"` from RNFBInstallationsModule.m. The symbols
  are already provided by the conditional import block above (via
  <Firebase/Firebase.h> on CocoaPods or @import FirebaseInstallations
  on SPM). The quoted header path was a CocoaPods-only artifact that
  could fail to resolve in SPM mode.

Author: jsnavarroc

packages/analytics/RNFBAnalytics.podspec

@@ -62,7 +62,7 @@ Pod::Spec.new do |s|
     firebase_dependency(s, firebase_sdk_version, ['FirebaseAnalytics'], 'FirebaseAnalytics/Core')
   end
 
-  unless defined?(spm_dependency)
+  unless defined?(spm_dependency) && !defined?($RNFirebaseDisableSPM)
     # CocoaPods-only: conditional IdentitySupport subspec
     if defined?($RNFirebaseAnalyticsWithoutAdIdSupport) && ($RNFirebaseAnalyticsWithoutAdIdSupport == true)
       Pod::UI.puts "#{s.name}: Not installing FirebaseAnalytics/IdentitySupport Pod, no IDFA will be collected."

packages/installations/ios/RNFBInstallations/RNFBInstallationsModule.m

@@ -26,8 +26,6 @@
 #import "RNFBApp/RNFBSharedUtils.h"
 #import "RNFBInstallationsModule.h"
 
-#import "FirebaseInstallations/FIRInstallations.h"
-
 @implementation RNFBInstallationsModule
 #pragma mark -
 #pragma mark Module Setup