Fix: Add Proper Catalog Support to Engine Adapter

[eakmanrq]

Controversial change to highlight: Removed the field catalog_name and instead let callers provide a TableName which means it can either be a string or exp.Table object.

Added engine adapter methods:

• get_current_catalog
• set_current_catalog

New Property: CatalogSupport
This tells the set_catalog decorator what level of catalog support the engine adapter has in order to set the catalog properly. 3 levels:

• Unsupported
• Requires Set Catalog
• Full Support

Requires Set Catalog means that operations cannot be provided with the catalog but instead they need set_current_catalog against the catalog and then they can provide the operation but now with the catalog dropped. This always refers to the target of the operation (ex: if drop schema, the schema being drooped) and we assume reads can happen across catalogs. For engines that don't support reads across catalogs we just consider them Unsupported (ex: Postgres).

Follow up work:

• Have new default catalog integrate with connector default catalog if it supports it
• Add Redshift catalog support
  • The challenge with this is that Redshift doesn't allow changing the catalog from within a connection. A new connection needs to be created with the new catalog defined. This is just for creating objects across catalogs and not querying across catalogs

[tobymao]

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