fix(db): keep migration checksums stable

Issue #155 removed the sqlx 0.8 rebuild workarounds by editing migrations
0007, 0014 and 0021 in place. Editing an applied migration changes its
checksum, and `migrate()` refuses to run when one no longer matches what
`_sqlx_migrations` recorded, so the daemon exited on startup against any
database that had already applied them — production included.

The sqlx 0.9 bump is the fix and survives: a new migration can carry
`-- no-transaction` so `PRAGMA foreign_keys = OFF` holds and a table
rebuild stops cascade-deleting its children. Only the retroactive cleanup
of migrations that already ran is reverted, along with #153's
`CHECK (title <> '')`, which rode on the 0021 edit and needs a migration
of its own rather than a rewrite of history.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

crates/arr-db/migrations/0007_movie_state_canonical.sql

@@ -1,13 +1,13 @@
--- no-transaction
 -- #73. movies.state used missing|grabbed|imported, predating arr-core's
 -- canonical MediaState vocabulary (missing|downloading|available) that
 -- series/episodes (0005) already follow.
 --
--- SQLite can't ALTER a CHECK constraint, so this rebuilds the table. It runs
--- outside a transaction (#155) so `PRAGMA foreign_keys = OFF` takes effect
--- and dropping the old `movies` does not cascade into `movie_releases`.
+-- SQLite can't ALTER a CHECK constraint, so this rebuilds the table -- which
+-- means dropping the old copy. `movie_releases` references it with
+-- ON DELETE CASCADE, so the drop would take its rows down too; stash them
+-- first and restore them once the new `movies` exists with the same ids.
 
-PRAGMA foreign_keys = OFF;
+CREATE TABLE movie_releases_backup AS SELECT * FROM movie_releases;
 
 CREATE TABLE movies_new (
     id                INTEGER PRIMARY KEY,
@@ -68,4 +68,6 @@ BEGIN
     SELECT RAISE(ABORT, 'movies require a movie root');
 END;
 
-PRAGMA foreign_keys = ON;
+INSERT INTO movie_releases SELECT * FROM movie_releases_backup;
+
+DROP TABLE movie_releases_backup;

crates/arr-db/migrations/0014_parked_state.sql

@@ -1,15 +1,11 @@
--- no-transaction
 -- #108: a vanished torrent must not re-grab. Overrides #86, which reopened
 -- the gap (state = 'missing', wanted untouched) so the next tick re-grabbed
 -- the same release. Adds 'parked' so the daemon can clear `wanted` and mark
 -- the title honestly instead — distinct from 'missing' (an open gap) and
 -- 'available' (satisfied). SQLite cannot alter a CHECK, so both tables are
 -- rebuilt (see 0007).
---
--- #155: runs outside a transaction so `PRAGMA foreign_keys = OFF` takes
--- effect and dropping the old tables does not cascade into their children.
 
-PRAGMA foreign_keys = OFF;
+CREATE TABLE movie_releases_backup AS SELECT * FROM movie_releases;
 
 CREATE TABLE movies_new (
     id                INTEGER PRIMARY KEY,
@@ -67,6 +63,11 @@ BEGIN
     SELECT RAISE(ABORT, 'movies require a movie root');
 END;
 
+INSERT INTO movie_releases SELECT * FROM movie_releases_backup;
+DROP TABLE movie_releases_backup;
+
+CREATE TABLE episode_releases_backup AS SELECT * FROM episode_releases;
+
 CREATE TABLE episodes_new (
     id               INTEGER PRIMARY KEY,
     season_id        INTEGER NOT NULL REFERENCES seasons (id) ON DELETE CASCADE,
@@ -101,4 +102,5 @@ CREATE INDEX episodes_pending_search
 
 CREATE INDEX episodes_state ON episodes (state);
 
-PRAGMA foreign_keys = ON;
+INSERT INTO episode_releases SELECT * FROM episode_releases_backup;
+DROP TABLE episode_releases_backup;

crates/arr-db/migrations/0021_episode_title_required.sql

@@ -1,51 +1,11 @@
--- no-transaction
 -- #153. `episodes.title` accepted the empty string, which TMDB sends for an
 -- unaired episode it has not named yet. Empty titles leaked into §9.2's
 -- search haystack, §7.4 filenames and the compat shim as if they were real
 -- text. Rows already carrying `''` take the same "TBA" placeholder the TMDB
 -- boundary now substitutes — #121's guarded update replaces it once TMDB
--- fills the title in — and the rebuilt table enforces non-empty with a
--- CHECK. The rebuild runs outside a transaction (#155) so
--- `PRAGMA foreign_keys = OFF` takes effect and dropping the old `episodes`
--- does not cascade into `episode_releases`.
-
+-- fills the title in.
+--
+-- A hard CHECK (title <> '') would need a table rebuild with foreign_keys
+-- off, which sqlx 0.8's migrator cannot run (it always wraps a migration in
+-- a transaction, where that pragma is a no-op); enforcement lives in code.
 UPDATE episodes SET title = 'TBA', updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now') WHERE title = '';
-
-PRAGMA foreign_keys = OFF;
-
-CREATE TABLE episodes_new (
-    id               INTEGER PRIMARY KEY,
-    season_id        INTEGER NOT NULL REFERENCES seasons (id) ON DELETE CASCADE,
-    number           INTEGER NOT NULL CHECK (number >= 0),
-    title            TEXT NOT NULL CHECK (title <> ''),
-    air_date         TEXT,
-    wanted           INTEGER NOT NULL DEFAULT 0 CHECK (wanted IN (0, 1)),
-    state            TEXT NOT NULL DEFAULT 'missing'
-                     CHECK (state IN ('missing', 'downloading', 'available', 'parked')),
-    search_attempts  INTEGER NOT NULL DEFAULT 0,
-    last_searched_at TEXT,
-    created_at       TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now')),
-    updated_at       TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now')),
-    vanished         INTEGER NOT NULL DEFAULT 0 CHECK (vanished IN (0, 1)),
-    UNIQUE (season_id, number)
-) STRICT;
-
-INSERT INTO episodes_new (
-    id, season_id, number, title, air_date, wanted, state, search_attempts,
-    last_searched_at, created_at, updated_at, vanished
-)
-SELECT
-    id, season_id, number, title, air_date, wanted, state, search_attempts,
-    last_searched_at, created_at, updated_at, vanished
-FROM episodes;
-
-DROP TABLE episodes;
-ALTER TABLE episodes_new RENAME TO episodes;
-
-CREATE INDEX episodes_pending_search
-    ON episodes (last_searched_at)
-    WHERE wanted = 1 AND state = 'missing';
-
-CREATE INDEX episodes_state ON episodes (state);
-
-PRAGMA foreign_keys = ON;

crates/arr-db/src/lib.rs

@@ -419,55 +419,6 @@ mod tests {
         );
     }
 
-    /// #153: an empty episode title takes the TBA placeholder during 0021's
-    /// backfill, and the rebuilt table's CHECK rejects new empty titles.
-    #[tokio::test]
-    async fn empty_episode_titles_are_backfilled_and_then_rejected() {
-        let dir = tempfile::tempdir().expect("tempdir");
-        let db = Db::connect(dir.path().join("arr.db"))
-            .await
-            .expect("connect");
-
-        MIGRATOR
-            .run_to(20, db.pool())
-            .await
-            .expect("migrations before the #153 backfill");
-
-        let series_id = sqlx::query(
-            "INSERT INTO series (tmdb_id, title, root_id)
-             SELECT 82728, 'Bluey', id FROM roots WHERE kind = 'tv' LIMIT 1",
-        )
-        .execute(db.pool())
-        .await
-        .expect("series")
-        .last_insert_rowid();
-        let season_id = sqlx::query("INSERT INTO seasons (series_id, number) VALUES (?, 1)")
-            .bind(series_id)
-            .execute(db.pool())
-            .await
-            .expect("season")
-            .last_insert_rowid();
-        sqlx::query("INSERT INTO episodes (season_id, number, title) VALUES (?, 1, '')")
-            .bind(season_id)
-            .execute(db.pool())
-            .await
-            .expect("empty title, valid before 0021");
-
-        db.migrate().await.expect("remaining migrations");
-
-        let title: String = sqlx::query_scalar("SELECT title FROM episodes")
-            .fetch_one(db.pool())
-            .await
-            .expect("episode row survives the rebuild");
-        assert_eq!(title, "TBA");
-
-        sqlx::query("INSERT INTO episodes (season_id, number, title) VALUES (?, 2, '')")
-            .bind(season_id)
-            .execute(db.pool())
-            .await
-            .expect_err("the rebuilt column rejects the empty string");
-    }
-
     #[tokio::test]
     async fn seeds_two_tv_roots_with_distinct_policies() {
         let (_dir, db) = fresh().await;