Update API Coverage

Update API coverage badges

The API Coverage badge for each module in the README's Available libraries table is the percentage of public firebase-android-sdk API members that this SDK invokes:

coverage = (Android SDK members invoked from the module's androidMain sources)
           / (all public, non-deprecated members in the module's api.txt on main)

The Android API surface comes from https://github.com/firebase/firebase-android-sdk/blob/main/firebase-<module>/api.txt.

Steps

1. From the repository root run:

   python3 .claude/skills/update-api-coverage/api_coverage.py --write
   

   It downloads each api.txt from the main branch of firebase-android-sdk, computes the percentages, prints a table, and rewrites the badge for every module it knows about in README.md. Add -v to see which members of each class are counted as used or missing, and --exclude-pipeline to leave out the Firestore Pipeline API (a large, separately-gated surface that this SDK does not wrap). If GitHub raw content is unreachable, save the api.txt files as <module>.txt in a directory and pass --api-dir DIR.

2. Review git diff README.md. Badge colour is green above 60%, orange otherwise.

3. Commit the README change.

Counting rules (implemented in api_coverage.py)

• A member is one of ctor, method, field, enum_constant, or property in api.txt. Overloads collapse to one entry per (class, name). @Deprecated, @RestrictTo, non-public members, annotation types, Companion and INSTANCE are excluded. A Kotlin property and its synthetic getX/setX/isX count once.
• A member is invoked when the module's src/androidMain Kotlin calls it (name(, name {, ::name), reads or writes it as a Kotlin property (.x for getX, .isX, .x = for setX), references a field or enum constant by name, or constructs the class. Declarations in the wrapper (fun name(, val name) do not count.
• Every member of an Android class exposed through a public actual typealias (exceptions, enums such as Direction, ChangeType, FunctionsExceptionCode) counts as invoked, because users get the whole class.
• Firestore Pipeline* classes and the com.google.firebase.firestore.pipeline packages count as unused unless the module sources mention "pipeline", to avoid false matches on generic names such as where and limit.

Authentication and Analytics (no api.txt)

These two Android libraries are closed source and have no module in firebase-android-sdk, so the script lists their API from the AARs instead (this reproduces the method used in PR #874: Authentication 166/314 = 53%, Analytics 26/160 = 16%). It needs javap from a JDK and access to Google Maven:

1. The BOM version is read from gradle/libs.versions.toml and the BOM POM is fetched from https://dl.google.com/dl/android/maven2/ to resolve the library versions (BOM 34.18.0: firebase-auth 24.2.0, firebase-analytics 23.2.0).
2. The AARs are downloaded and classes.jar extracted:
   • Authentication: com.google.firebase:firebase-auth, package com.google.firebase.auth.
   • Analytics: the firebase-analytics AAR is an empty shim, so the script reads the play-services-measurement-api version from the firebase-analytics POM and downloads com.google.android.gms:play-services-measurement-api (23.2.0 for BOM 34.18.0), package com.google.firebase.analytics.
3. javap -v runs over every class in that package and its sub-packages except internal and connector. Non-public, synthetic, bridge and deprecated members are dropped, as are obfuscated zz* names, $-suffixed helpers, anonymous and lambda classes, and enum values/valueOf. The result feeds the same counting rules as the api.txt modules; the Kotlin facade classes (FirebaseAuthKt, AnalyticsKt) and DSL receivers such as ConsentBuilder are ordinary classes here and count by member name.
4. The Analytics total includes the 118 string constants on FirebaseAnalytics.Event, Param and UserProperty, which the Kotlin SDK does not expose. They stay in for consistency with the api.txt badges, which count constants too.

If Google Maven is blocked in the sandbox, download the two AARs elsewhere, put them in a directory as firebase-auth-<version>.aar and play-services-measurement-api-<version>.aar, and pass --aar-dir DIR. If that is not possible either, run the script for the other modules only (api_coverage.py --write database firestore ...) and say the two badges were not recalculated rather than estimating them.