refactor(workspace): enforce layered crate boundaries

crates/aether-data/runtime/src/lifecycle/backfill.rs

@@ -0,0 +1,25 @@
+#[cfg(feature = "mysql")]
+mod mysql;
+#[cfg(feature = "postgres")]
+mod postgres;
+#[cfg(feature = "sqlite")]
+mod sqlite;
+mod types;
+
+#[cfg(all(test, feature = "postgres", feature = "mysql", feature = "sqlite"))]
+mod tests;
+
+#[cfg(feature = "mysql")]
+pub use mysql::{
+    pending_backfills as pending_mysql_backfills, run_backfills as run_mysql_backfills,
+};
+#[cfg(feature = "postgres")]
+pub use postgres::{pending_backfills, run_backfills};
+#[cfg(feature = "sqlite")]
+pub use sqlite::{
+    pending_backfills as pending_sqlite_backfills, run_backfills as run_sqlite_backfills,
+};
+pub use types::PendingBackfillInfo;
+
+#[cfg(all(test, feature = "postgres", feature = "mysql", feature = "sqlite"))]
+use postgres::{pending_backfills_from_applied, AppliedBackfill};