FooterMode::RowCount and FooterMode::Auto should use the number of *rendered* rows

Context

config.footer_mode can be set to a number N, in which case columns in tables will have footers rendered only if the table contains N or more records. This maps to the variant FooterMode::RowCount in Rust. For example:

footer_mode can also be set to "auto", which corresponds to FooterMode::Auto. In theory this should add a footer when the number of records exceeds the terminal height. However, it looks like this is not currently implemented and "auto" does nothing.

Problem

This approach breaks down when individual records span multiple terminal rows. For example, the output of scope commands | first 4 is taller than my entire monitor!

I do not want footers for a table that is only 4 rows tall when rendered, but if a table is too tall to fit in my terminal all at once I definitely do want footers.

Solution

Both RowCount and Auto should use the height of the table as rendered when determining whether to display a footer. For example:

1. RowCount(10): If a table only contains 1 record but is rendered as 10+ rows tall because it contains multiline text, it will be rendered with a footer
2. Auto: If a table is taller than the current terminal height when rendered, it will be rendered with a footer no matter how many records it has

This will probably require some changes to our table rendering code to pull off.

Start with the config.footer_mode handling and the FooterMode::RowCount and FooterMode::Auto variants, then trace the table rendering code. Use examples such as scope commands | first 4 to compare record counts with rendered height; done means both modes decide whether to show footers from the rendered table height, including multiline records and terminal height for Auto.