fix: prevent state table collision by including system/user prefix

[ShashidharM0118]

This PR fixes a bug where StateTable and CachingStateTable were only using the raw ID for equality checks, ignoring the system/user prefix. This could lead to data corruption if a user-defined state tag happened to share the same ID as a system-defined one.

Changes:

• Added getIdWithPrefix() to the StateTag interface to expose the full identifier.
• Updated StateTags.ID_EQUIVALENCE and SimpleStateTag to incorporate the prefix in equality and hash calculations.
• Modified CachingStateTable to use the prefixed ID in its internal StateTableKey.
• Added unit tests to verify that tags with the same ID but different prefixes no longer collide.

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Fixes #36753

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[gemini-code-assist]

Summary of Changes

Hello @ShashidharM0118, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a critical bug in state management where StateTable and CachingStateTable could experience collisions between system-defined and user-defined state tags if they happened to share the same raw identifier. By introducing a mechanism to include a system/user prefix in state tag identifiers, the changes ensure that each state tag has a globally unique key, thereby preventing data corruption and enhancing the robustness of state handling within the system.

Highlights

• Introduced Prefixed State Tag IDs: Added a new default method, getIdWithPrefix(), to the StateTag interface. This method provides a unique identifier that includes a system/user prefix, crucial for distinguishing state tags.
• Updated State Tag Equivalence Logic: Modified StateTags.ID_EQUIVALENCE and the SimpleStateTag inner class to utilize the new prefixed ID for accurate equality checks and hash code calculations, ensuring proper identification.
• Prevented State Table Collisions: Updated CachingStateTable to use the prefixed ID when creating StateTableKey instances. This resolves a bug where system and user-defined state tags with identical raw IDs could collide, leading to data corruption.
• Enhanced Test Coverage: Added new unit tests to StateTagTest.java to validate the functionality of getIdWithPrefix() and confirm that state tags with the same raw ID but different prefixes are correctly distinguished, preventing unintended collisions.

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