fix(db): add user foreign key constraint to annotation table (#4211)

* fix(db): add user foreign key constraint to annotation table

Associates user_id with user.id, with cascade for delete (drop annotation) and update (update annotation).
Migration script will only copy/insert annotations for user IDs that exist

* remove default for user_id

* refactor(db): rename migration correct sequencing

Signed-off-by: Deluan <deluan@navidrome.org>

---------

Signed-off-by: Deluan <deluan@navidrome.org>
Co-authored-by: Deluan <deluan@navidrome.org>

db/migrations/20250701010102_add_annotation_user_foreign_key.sql

@@ -0,0 +1,46 @@
+-- +goose Up
+-- +goose StatementBegin
+CREATE TABLE IF NOT EXISTS annotation_tmp
+(
+	user_id     varchar(255)    not null
+        REFERENCES user(id)
+            ON DELETE CASCADE
+            ON UPDATE CASCADE,
+	item_id     varchar(255)    default '' not null,
+	item_type   varchar(255)    default '' not null,
+	play_count  integer         default 0,
+	play_date   datetime,
+	rating      integer         default 0,
+	starred     bool            default FALSE not null,
+	starred_at  datetime,
+	unique (user_id, item_id, item_type)
+);
+
+
+INSERT INTO annotation_tmp(
+    user_id, item_id, item_type, play_count, play_date, rating, starred, starred_at
+)
+SELECT user_id, item_id, item_type, play_count, play_date, rating, starred, starred_at
+FROM annotation
+WHERE user_id IN (
+    SELECT id FROM user
+);
+
+DROP TABLE annotation;
+ALTER TABLE annotation_tmp RENAME TO annotation;
+
+CREATE INDEX annotation_play_count
+    on annotation (play_count);
+CREATE INDEX annotation_play_date
+    on annotation (play_date);
+CREATE INDEX annotation_rating
+    on annotation (rating);
+CREATE INDEX annotation_starred
+    on annotation (starred);
+CREATE INDEX annotation_starred_at
+    on annotation (starred_at);
+
+-- +goose StatementEnd
+
+-- +goose Down
+