fix(android): allow older Kotlin compilers with ads SDK 25.4

[floze-the-genius]

Description

Google Mobile Ads 25.3+ embeds Kotlin 2.3 metadata even though this module only consumes its public Java API. That makes the library fail to compile in Expo and React Native projects still using Kotlin 2.1.x.

Configure only this library's KotlinCompile tasks to skip the dependency metadata version check. This preserves the Android AgeRestrictedTreatment API added with the newer SDK without forcing every consumer module to upgrade to Kotlin 2.3.

Related issues

Fixes #863

Release Summary

Allow Android projects using Kotlin 2.1.x to compile with Google Mobile Ads SDK 25.4.0.

Checklist

• I read the Contributor Guide and followed the submission process.
  • Yes
• My change supports the following platforms;
  • Android
  • iOS
• My change includes tests;
  • e2e tests added or updated in __tests__e2e__
  • jest tests added or updated in __tests__
• I have updated TypeScript types that are affected by my change.
• This is a breaking change;
  • Yes
  • No

Test Plan

• Reproduced the failure in a focused Gradle harness using Kotlin 2.1.0 and the exact play-services-ads:25.4.0 AAR classes.
• Verified the same harness compiles after applying the scoped -Xskip-metadata-version-check configuration in Groovy.
• yarn tests:jest --runInBand (7 suites passed, 79 tests passed)
• yarn tsc:compile
• yarn lint

A full Android example assemble was not run locally because this machine has no accepted Android SDK installation; the repository Android CI remains the end-to-end build check.

🔥

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ mikehardy
❌ floze-the-genius
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[mikehardy]

thanks @floze-the-genius! clever fix for a problem that's sure to hit most folks at the moment. I added a quick follow-up and I'll be happy to merge if you can sign the CLA, thanks!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 39.35%. Comparing base (a34c7ba) to head (12b606c).
⚠️ Report is 246 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #866      +/-   ##
==========================================
- Coverage   43.72%   39.35%   -4.37%     
==========================================
  Files          30       36       +6     
  Lines         549      671     +122     
  Branches      151      172      +21     
==========================================
+ Hits          240      264      +24     
- Misses        309      407      +98     

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[mikehardy]

there is no problem merging this despite iOS build failing - it's failing for unrelated reasons

still need a CLA sign from @floze-the-genius though, otherwise we'll have to recreate this PR separately...