Feature: basecamp cards done - complete a card from CLI

[pravashkarki]

Problem

There is no CLI command to properly complete a Kanban card. basecamp done <id> only works on todos - when used on a card it silently does nothing useful (doesn't move the card to the Done column).

To complete a card today, you need to:

1. Look up the card table's Done column ID with basecamp cards columns
2. Move the card with basecamp cards move <id> --to <done_column_id>
3. Optionally remove the assignee and clear the due date

This is error-prone and requires knowing internal column IDs.

Proposed Solution

basecamp cards done <id> [--in <project>]

This should:

• Find the Done column in the card's table automatically
• Move the card to that column
• Optionally clear the due date and assignee (or add flags for this)

Alternatively, basecamp done could detect whether the ID is a todo or a card and handle both correctly.

Context

This came up repeatedly in daily Basecamp operations via the CLI - managing cards across multiple projects where each card table has its own Done column ID.