Unhandled fatal errors if db operations called outside backdrop root and without specifying root

[yorkshire-pudding]

Steps to reproduce

1. Navigate outside the Backdrop root
2. run bee db-drop
3. run bee db-export
4. run bee db-import (with a valid file)
5. run bee sql

Expected result A useful error message such as that for bee status:

 ⚠️  No Backdrop installation found. Run this command again from within a Backdrop installation, or use the '--root' global option.

Actual result Fatal errors such as:

user@machine:~/projects/bee$ lando bee sql
PHP Fatal error:  Uncaught Error: Class "Database" not found in /app/commands/db.bee.inc:279
Stack trace:
#0 /app/includes/command.inc(107): sql_bee_callback(Array, Array)
#1 /app/bee.php(31): bee_process_command()
#2 {main}
  thrown in /app/commands/db.bee.inc on line 279

Fatal error: Uncaught Error: Class "Database" not found in /app/commands/db.bee.inc:279
Stack trace:
#0 /app/includes/command.inc(107): sql_bee_callback(Array, Array)
#1 /app/bee.php(31): bee_process_command()
#2 {main}
  thrown in /app/commands/db.bee.inc on line 279

Note: db-query is fine. it returns:

 ✘  The required bootstrap level for 'db-query' is not ready.