Compile-time gate that fails the build when declared schemas have drifted from the migration history.

The runtime sibling, kura_schema_verify:verify/1,2, catches drift in production. This provider catches it earlier — at PR review time in CI — by computing the same diff kura compile would compute and exiting non-zero if anything is missing.

rebar3 kura check       # exit 1 with a drift report, or 0 if clean

Use it as a CI step right after build. Anybody who edits a schema without regenerating a migration (or any tool that generates an incomplete diff) gets a red build instead of a silent landmine.