What this PR does / why we need it:

This PR adds online feature view versioning support for the SingleStore online store when registry.enable_online_feature_view_versioning is enabled.

It updates SingleStore’s table routing to read/write from versioned namespaces (e.g. {project}_{feature_view}_v{N}) so version-qualified refs like driver_stats@v1:avg_daily_trips can be served from the correct underlying online table. It also updates the global online-store guard to allow version-qualified reads for SingleStore (and still reject unsupported stores) when versioning is enabled.

Additionally, it adds an integration/universal test covering SingleStore version-qualified reads.

Which issue(s) this PR fixes:

Fixes #6181

Checks

• I've made sure the tests are passing.
• My commits are signed off (git commit -s)
• My PR title follows conventional commits format

Testing Strategy

• Unit tests
• Integration tests
• Manual tests
• Testing is not required for this change

Misc

Notes:

• Version-qualified reads are only allowed when registry.enable_online_feature_view_versioning is enabled; otherwise VersionedOnlineReadNotSupported is raised.
• The new SingleStore integration/universal test may be skipped locally if the universal SingleStore environment is not part of the parametrized test matrix (it should run in CI where SingleStore is enabled).