firebase/firebase-ios-sdk 12.15.0 on GitHub

The Firebase Apple SDK (12.15.0) is now available. For more details, see
the Firebase Apple SDK release notes.

What's Changed

[Core] Require swift-tools-version:6.1 in Package.swift by @andrewheard in #16223
[AI] Rename GeminiModel to GeminiLanguageModel by @andrewheard in #16227
fix(appcheck): remove redundant fac debug token logging by @ncooke3 in #16197
feat(appcheck): Add new internal, default provider by @ncooke3 in #16190
docs(appcheck): prefer 'AppCheckDebugToken' for debug env var injection by @ncooke3 in #16230
feat(appcheck): add helpful log for registering debug tokens by @ncooke3 in #16232
[AI] Add Hashable conformance to model config types by @andrewheard in #16233
[AI] Add public init for GeminiLanguageModel by @andrewheard in #16234
feat(ai): add app check dependency by @ncooke3 in #16185
Readme improvements by @paulb777 in #16238
[AI] Revert rename of GeminiModel to GeminiLanguageModel by @andrewheard in #16237
Migrate repo dev content from README to CONTRIBUTING by @paulb777 in #16239
[AI] Add readme banner for FMF adapter by @paulb777 in #16248
Analytics 12.15.0 by @htcgh in #16250
fix(firestore): remove designated initializers for force_index by @dlarocque in #16229
fix(ai): Handle Xcode 27 LanguageModelSession.Error collision by @andrewheard in #16257
feat(appcheck): implement RecaptchaEnterpriseProvider and tests by @ncooke3 in #16155
[AI] Support SpeechConfig in Text-To-Speech by @milaGGL in #16226
try building docc docs on swift package index by @morganchen12 in #16262

Full Changelog: 12.14.0...12.15.0