Reorg basic usage from quickstart to table management

[prrao87]

Some observations and ideas for reorg that I think would make the flow cleaner.

The current page working with tables just has a summary of all its subpages. It's not that gradual a leap from the quickstart (which is very basic) to the "Table management" section of the user guide.

Here's my proposal to make this smoother:

• Rename the "Working with Tables" under the user guide to "Table management" - this is what the section's really about - the section walks the user through how to manage tables
• Rename the page "working with tables" to be just "Table management" - i.e., reverse the naming of the section with the first page in the section, because this page is actually about working with tables (Creating, deleting and dropping tables) 😅
• Move the "basic usage" page from the quickstart to be the first page of the "Table management" section. This makes sense imo because basic usage is also about working with tables, and it builds upward from the quickstart example (which is too simple), and it gradually leads into more complex tasks like altering columns and schema management in tables.

In summary, "Quickstart" doesn't need to be a directory, it can be just an ultra-basic into (hello world) to LanceDB in Python, TypeScript and Rust. The section "Table management" will have many more advanced features that the UX will be gradually built up towards, with the "basic usage" section being a bridge.