Rewrite useTableDefinitions hook as getTableDefinitions util

[doeg]

Signed-off-by: Sara Bee 855595+doeg@users.noreply.github.com

Description

This rewrites the Schema[] -> TableDefinition[] logic as a utility function instead of a query hook. This feels like a better separation of concerns (more reusable + easier to test), albeit slightly less convenient (since components need to call, and usually memoize, the getTableDefinitions transform).

One note is that getTableDefinitions now returns tables that define table_size but not table_definition. This unearthed a minor bug, #7820. The user-facing behaviour is that tables that have a size but no table definition will link to a schema detail route that 404s, even though the table technically exists. As described in #7820, once the bug is fixed the front-end won't need to conflate the existence of the table_definition property with whether the table exists, and these links will no longer 404.

Related Issue(s)

N/A

Checklist

• Should this PR be backported? No
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

N/A

Impacted Areas in Vitess

Components that this PR will affect:

• Query Serving
• VReplication
• Cluster Management
• Build/CI
• VTAdmin