dataconnect(chore): add last_update_sequence_number to cache db

[dconeybe]

This pull request introduces a new last_update_sequence_number column to the Data Connect SQLite cache database for queries and entities. This sequence number tracks the order of cache updates and will be used by subsequent work to avoid publishing duplicate query results from cache in realtime query subscriptions.

Highlights

• Monotonic Sequence Tracking: Configured DataConnectCacheDatabase to generate monotonically increasing sequence numbers using a sequence helper table, assign them to queries and entities during update transactions, and report the maximum sequence number across a query and all of its referenced entities upon retrieval.
• Incremental Database Schema Migrator: Upgraded the cache database schema to version 1.1.0 and structured the schema migrator to perform incremental multi-step migrations, starting with database creation at 1.0.0 and applying the migration to 1.1.0 which adds the last_update_sequence_number columns.
• Lexicographical Byte Array Ordering: Conformed ImmutableByteArray to the Comparable interface, supported by a backport of signed lexicographical byte array comparison (contentCompareTo) to ensure compatibility with Android versions below API level 33.
• Comprehensive Integration and Unit Tests: Added regression tests for database migration and verification of database state, along with thorough testing of correct sequence number calculation and stable byte array sorting.

Changelog

• DataConnectCacheDatabase.kt
  • Added last_update_sequence_number tracking logic, including the SqliteSequenceNumber inline value class, sequence number generation helper, and maximum last update sequence number computation during query rehydration.
• DataConnectCacheDatabaseMigrator.kt
  • Upgraded the database schema version to 1.1.0, introduced an incremental migration runner loop, and implemented step migration from 1.0.0 to 1.1.0 to alter queries and entities tables.
• ByteArrayUtils.kt
  • Created a utility file that backports signed lexicographical byte array comparison (contentCompareTo) for Android devices running on API levels below 33.
• ImmutableByteArray.kt
  • Conformed ImmutableByteArray to the Comparable<ImmutableByteArray> interface, utilizing the new contentCompareTo logic to achieve a stable cross-process sort order.
• DataConnectCacheDatabaseMigratorUnitTest.kt
  • Added integration tests verifying that existing data is preserved during progressive 1.0.0 to 1.1.0 migrations, and that proper exceptions are thrown when the database version or application ID is unrecognized.
• DataConnectCacheDatabaseUnitTest.kt
  • Added unit tests verifying proper sequence number updates during query insertion and verifying sequence number retrieval logic, including edge cases with null database values.
• ImmutableByteArrayUnitTest.kt
  • Added property and unit tests for the newly introduced comparison behaviors of ImmutableByteArray, covering identical arrays, prefixes, and different array lengths.
• CartesianProduct.kt
  • Added a utility function to compute the cartesian product of two iterables to support unit testing.
• TestValueGenerator.kt
  • Added a utility class to facilitate deterministic test sample generation from Kotest arbitrary data generators (Arb) outside of standard property-based tests.

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[dconeybe]

/gemini review

[github-actions]

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[gemini-code-assist]

Code Review

This pull request introduces sequence numbers (SqliteSequenceNumber) to track updates for queries and entities in the SQLite cache database, migrating the schema from version 1.0.0 to 1.1.0. It also adds a lexicographical comparison utility for byte arrays to support comparing ImmutableByteArray instances on older Android API levels. The review feedback highlights opportunities to simplify string concatenations by removing redundant empty strings in DataConnectCacheDatabaseMigrator.kt.