Data Integration

Add data storage integration as an optional lightweight module (no one likes a /msg plugin that has 200 threads and a h2 database) in order to keep stage progression as persistent data

The issue names no files, tests, or entry points. Start by locating the stage-progression implementation and reviewing how tutorial state is currently held; then assess the optional lightweight storage module against the requirement that progression persist without forcing a large database dependency. Done means persistent stage progression is available through an optional integration.

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