Integrate Joe with DBLab

Goal

Use Database Lab Client SDK to provision Joe sessions.

TODO / How to implement

• Use Client SDK instead of provision code which duplicates Database Lab #90 (closed)
• Keep psql for psql commands available to users #92 (closed)
• Configure Database Lab connection instead of provision mode #93 (closed)
• Idle sessions on the Joe side #95 (closed)
• Use new sync methods from Database Lab SDK
• Remove AWS part and other modes completely, use SDK instead

Can be separated from this list:

• Error refactoring #91
• Add linter #94

Acceptance criteria