[Release] Update CHANGELOGs for M175 (#15672)

Author: andrewheard

FirebaseAI/CHANGELOG.md

@@ -1,6 +1,8 @@
-# 12.7.0
+# 12.8.0
 - [feature] Added support for configuring thinking levels with Gemini 3 series
   models and onwards. (#15557)
+
+# 12.7.0
 - [fixed] Fixed support for API keys with iOS+ app
   [Bundle ID restrictions](https://docs.cloud.google.com/docs/authentication/api-keys#adding-application-restrictions)
   by setting the `x-ios-bundle-identifier` header. (#15475)

FirebasePerformance/CHANGELOG.md

@@ -1,4 +1,4 @@
-# Unreleased
+# 12.8.0
 - [fixed] Use UIScreen.maximumFramesPerSecond for dynamic slow frame threshold. (#10220)
 
 # 12.5.0

Firestore/CHANGELOG.md

@@ -1,6 +1,6 @@
-# Unreleased
+# 12.8.0
 - [fixed] Fix crash while fetching Auth and App Check tokens. (#15281)
-- [feature] `Pipeline` support is now available for the `Enterprise edition` as a public review feature. (#15625)
+- [feature] `Pipeline` support is now available for the `Enterprise edition` as a public preview feature. (#15625)
 - [fixed] Fixed an issue where the returned object in transaction blocks could not
   pass across actor boundaries in Swift 6 (#15467).