grammar+db: 3b — SQL INSERT grammar + minimal execution (ADR-0033 §1)

SQL_INSERT_SHAPE (INTO <table> [(cols)] VALUES tuple(s)) with __rdbms_*
target rejection; Command::SqlInsert{sql,target_table}; Request::RunSqlInsert
+ do_sql_insert worker (tx-guarded: execute, then finalize_persistence for
CSV + history before commit, so failures roll back and don't re-persist).
Auto-show is best-effort via last_insert_rowid range.

Isolated behind a dev `sqlinsert` entry word (Advanced) so the SQL path is
testable without making `insert` a shared word yet (that's 3j, after 3d
auto-fill parity). Command::SqlInsert carries only sql+target_table; the
plan's listed_columns/returning land in 3d/3g where they're read.

6 grammar accept/reject tests + 8 integration tests (single/multi-row,
column-list, full-arity, history, rollback-on-failure, multi-row atomicity,
parse-path reconstruction, internal-table rejection). 1452 baseline green.

src/app.rs

@@ -1468,6 +1468,12 @@ impl App {
             // no single table name to fall back on. A query
             // failure routes through `Operation::Query`.
             C::Select { .. } => (Operation::Query, None, None),
+            // A SQL `INSERT` (ADR-0033) — route engine errors
+            // (FK / UNIQUE / NOT NULL) through the insert operation
+            // with the parsed target table.
+            C::SqlInsert { target_table, .. } => {
+                (Operation::Insert, Some(target_table.as_str()), None)
+            }
             C::Replay { .. } => (Operation::Replay, None, None),
             // An `explain` failure (e.g. unknown table) is best
             // described by the wrapped query it failed to plan.