Add rename_indexes_for_table partitioning helper

What does this MR do and why?

Adds the indexes_by_definition_for_table and rename_indexes_for_table database partitioning migration helper methods.

These methods allow you to capture the index names for indexes on a table, then restore those names after an operation has regenerated the index names.

This is needed when making a table the first partition of itself, where the index names change as you go through this ALTER/CREATE workflow:

graph TD
    A[index_table_on_created_at] -->|ALTER TABLE table RENAME TO table_1| B
    B[index_table_on_created_at]
    B -->|"CREATE TABLE table (LIKE table_1 INCLUDING ALL)"| C
    C[table_created_at_idx]

Relates to #370274 (closed)

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