feat(history): mode-tagged history + top-of-chain journaling (#30)

Record the submission mode per history entry so advanced commands are
reusable in simple mode, and fix the bug where a ':'-one-shot command
lost its ':' across sessions (ADR-0052, closing #30).

Format: the history.log status token gains an optional ':adv' suffix
(ok / ok:adv / err / err:adv); 'source' stays last and canonical, so
replay is unaffected. The in-memory ring (still Vec<String>) stores
advanced entries ': '-prefixed; recall strips the ':' in advanced mode
and keeps it in simple; hydration reconstructs the prefix from the tag.

Journaling moved from the worker to the dispatch layer (spawn_dsl_-
dispatch / run_replay / app-command sites), where the mode is in scope
with no worker plumbing; finalize_persistence writes only yaml/csv
(commit-db-last still atomic for state). The journal write is now
best-effort (command already committed), consistent with the failure
path. App commands journal simple, so they recall bare. Journaling is
now uniform (every successful command, per ADR-0034) — closing a gap
where show tables/relationships/explain didn't journal.

Amends ADR-0034 (status tag + journaling location), ADR-0015 §6
(history.log out of the worker tx), ADR-0040 (journal-write best-effort).
15 worker-level journaling tests retired, re-covered at the new layer
(history.rs format, app.rs recall matrix, iteration6 cross-session
regression, replay). 2471 pass / 0 fail / 0 skip, clippy clean.

tests/it/sql_create_index.rs

@@ -141,7 +141,7 @@ fn create_unique_index_on_duplicate_data_is_refused() {
 
 #[test]
 fn if_not_exists_on_an_existing_name_is_a_noop_and_journalled() {
-    let (p, db, _d) = open(false);
+    let (_p, db, _d) = open(false);
     let r = rt();
     make_t(&db, &r);
     r.block_on(db.sql_create_index(
@@ -169,8 +169,8 @@ fn if_not_exists_on_an_existing_name_is_a_noop_and_journalled() {
         CreateIndexOutcome::Skipped(name) => assert_eq!(name, "ix"),
         CreateIndexOutcome::Created(_) => panic!("expected Skipped, got Created"),
     }
-    let log = std::fs::read_to_string(p.path().join("history.log")).expect("read history.log");
-    assert!(log.contains(line), "the skipped create should be journalled; log:\n{log}");
+    // ADR-0052: journaling moved to the dispatch layer; this test now
+    // asserts only the no-op `Skipped` outcome.
 }
 
 #[test]