refactor(data): drop sqlite no-op migration

crates/aether-data/adapters/sqlite/migrations/20260827040000_expand_proxy_password_ciphertext.sql

@@ -1,2 +0,0 @@
--- SQLite proxy_password is already TEXT; keep migration ordering aligned across drivers.
-SELECT 1;

crates/aether-data/runtime/src/lifecycle/bootstrap/postgres.rs

@@ -8,8 +8,7 @@ use tracing::info;
 pub(crate) static EMPTY_DATABASE_SNAPSHOT_SQL: &str =
     include_str!(concat!(env!("OUT_DIR"), "/empty_database_snapshot.sql"));
 // Keep post-snapshot migrations executable on a fresh database so required
-// schema changes still run. Compatibility migrations after this frontier are
-// explicit no-ops and must not rewrite legacy rows.
+// schema changes after this frontier still run.
 pub(crate) const EMPTY_DATABASE_SNAPSHOT_CUTOFF_VERSION: i64 = 20260821130000;
 
 const PUBLIC_BASE_TABLE_COUNT_SQL: &str = r#"

crates/aether-data/runtime/src/lifecycle/migrate/tests.rs

@@ -1271,7 +1271,6 @@ fn mysql_and_sqlite_migrations_include_enabled_incrementals() {
             20260821000000,
             20260821120000,
             20260821130000,
-            20260827040000,
             20260827050000,
             20260831000000,
             20260831010000,