Format an Aligned Text Table

CLI tools print tables. Implement format_table(headers, rows) returning a string in exactly this format:

| name  | qty | price |
|-------|-----|-------|
| apple |   3 |  1.50 |
| kiwi  |  12 |  0.25 |

Rules:

• A column is numeric if every non-None value in it is an int or float (but not a bool). Numeric columns are right-aligned, including their header. Other columns are left-aligned.
• Floats are shown with 2 decimal places. None is shown as an empty cell. Everything else uses str().
• Each column is as wide as its widest cell or header, with one space of padding on each side.
• Lines are joined with "\n", with no trailing newline.