Add logic to handle end timestamp of mutable change stream bounded query

[chenxuesdu]

For mutable change stream bounded queries, Spanner only allow the max end timestamp to be 30 minutes in the future. So when user provided a end timestamp to read, we choose the min of max allow timestamp and the provided timestamp.

[gemini-code-assist]

Summary of Changes

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This pull request addresses a specific constraint in Google Cloud Spanner regarding mutable change stream bounded queries, where the end timestamp cannot exceed 30 minutes into the future. The changes introduce a mechanism to detect if a change stream is mutable and, if so, automatically adjust the provided end timestamp to comply with this limitation. This ensures that queries remain valid and prevents potential errors when users specify end timestamps beyond the allowed future window.

Highlights

• Mutable Change Stream Identification: A new isMutableChangeStream flag has been introduced and propagated through relevant classes (DaoFactory, ReadChangeStreamPartitionDoFn, QueryChangeStreamAction) to specifically identify and handle mutable change streams.
• Bounded Query End Timestamp Enforcement: Logic has been added to QueryChangeStreamAction to enforce Spanner's limitation on mutable change stream bounded queries. The end timestamp for such queries is now capped to a maximum of 30 minutes in the future from the current time, choosing the minimum between the user-provided timestamp and this limit.
• Code Structure and Dependency Injection: The isMutableChangeStream flag is passed as a constructor argument to QueryChangeStreamAction and initialized within ReadChangeStreamPartitionDoFn from DaoFactory, ensuring proper dependency injection and enabling conditional logic based on the change stream type.

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