fix: SDK 51-54 support — dynamic build.gradle, peer dep range, remove deprecated APIs

[maniac-tech]

Summary

Fixes compatibility issues preventing the library from working on Expo SDK 51–54.
Bumps version to 9.1.1.

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Changes

android/build.gradle

• Fixed minSdkVersion from 34 → 21 — the previous value was blocking any app targeting Android 5.0+, which is the vast majority of production apps
• Made compileSdk and targetSdkVersion dynamic via safeExtGet() — the library now defers to the host app's values instead of hardcoding them
• Changed react-native dependency from 0.73.6 → + — picks up the host app's bundled version at build time, preventing version conflicts
• Added Java 1.8 source/target compatibility

package.json

• Version: 9.0.2-alpha → 9.1.1
• peerDependencies: "react-native": "*" → ">=0.73" — accurately documents the minimum supported version (SDK 51 = RN 0.74) while staying compatible with all SDK 51–54 users
• Added keywords: expo, otp

RNExpoReadSmsPackage.java

• Removed deprecated createJSModules() override — this method was removed from the React Native API in RN 0.47 and its presence causes compile warnings/errors on newer RN versions

RNExpoReadSmsModule.java

• Added explicit Build import
• Set msgReceiver = null on stopReadSMS to prevent potential memory leaks
• Minor comment cleanup

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Testing

Verified against 4 TestApp branches:

• sdk-51 — Expo 51 / RN 0.74 — ExpoReadSMS-TestApp PR #22
• sdk-52 — Expo 52 / RN 0.76 — ExpoReadSMS-TestApp PR #23
• sdk-53 — Expo 53 / RN 0.79 — ExpoReadSMS-TestApp PR #24
• sdk-54 — Expo 54 / RN 0.81 — ExpoReadSMS-TestApp PR #25

Related

• Closes Fix "return_statements" issue in index.js #88 (SDK 51–54 support tracking issue)
• Part of Tier 1 of the New Architecture migration plan
• Tier 2 (SDK 55 / full New Arch via Expo Modules API) tracked separately

[maniac-tech]

Tested this with SDK versions 51 - 54. Good to merge,