⚡ Optimize storeReTrainedSms with DB Transaction

[google-labs-jules]

💡 What:

• Wrapped the loop in storeReTrainedSms within a SQLite transaction.
• Refactored updateInSms to accept an open SQLiteDatabase instance, preventing redundant initialization/uninitialization inside the loop.
• Added DatabaseBridgePerformanceTest.java to measure performance (and verify correctness).
• Fixed ExampleInstrumentedTest.java to use correct AndroidX imports.

🎯 Why:

• The previous implementation performed an individual database update for each SMS in the list. This "N+1" pattern is highly inefficient due to transaction overhead (fsync) for each operation.
• Using a single transaction for the batch reduces I/O significantly, likely improving performance by orders of magnitude for large lists.

📊 Measured Improvement:

• A benchmark test DatabaseBridgePerformanceTest was added.
• Note: Benchmark execution requires a connected Android device or emulator, which was not available in this environment. However, the optimization (Batch Transaction vs Individual Updates) is a standard and well-proven pattern for SQLite performance.

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PR created automatically by Jules for task 10253757382311930345 started by @xRahul

[google-labs-jules]

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