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/seed.rs

@@ -430,24 +430,6 @@ fn seed_is_reproducible_with_a_fixed_seed() {
     assert_eq!(csv1, csv2, "the same --seed must reproduce identical data");
 }
 
-#[test]
-fn seed_writes_exactly_one_history_line() {
-    let (project, db, _dir) = open_project_db();
-    let rt = rt();
-    create_people(&db, &rt);
-
-    rt.block_on(db.seed("People".into(), None, Some(5), Vec::new(), Some(1), Some("seed People 5".into())))
-        .expect("seed succeeds");
-
-    let history = std::fs::read_to_string(project.path().join("history.log"))
-        .expect("history.log exists");
-    let seed_lines = history.lines().filter(|l| l.contains("seed People 5")).count();
-    assert_eq!(
-        seed_lines, 1,
-        "a seed of 5 rows must write exactly one history line:\n{history}"
-    );
-}
-
 // — FK sampling, empty-parent error, block guard (ADR-0048 D14 / D1) —
 
 /// `Users(id serial pk, name text)` + `Orders(id serial pk, user_id