core: fix deleting user with chat tags (#6374)

* core: fix deleting user with chat tags

* schema, tests

* schema

* update simplexmq

* update ios

* plans

src/Simplex/Chat/Store/SQLite/Migrations/M20251017_chat_tags_cascade.hs

@@ -0,0 +1,30 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Store.SQLite.Migrations.M20251017_chat_tags_cascade where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20251017_chat_tags_cascade :: Query
+m20251017_chat_tags_cascade =
+  [sql|
+PRAGMA writable_schema=1;
+
+UPDATE sqlite_master
+SET sql = replace(sql, 'user_id INTEGER REFERENCES users', 'user_id INTEGER REFERENCES users ON DELETE CASCADE')
+WHERE name = 'chat_tags' AND type = 'table';
+
+PRAGMA writable_schema=0;
+|]
+
+down_m20251017_chat_tags_cascade :: Query
+down_m20251017_chat_tags_cascade =
+  [sql|
+PRAGMA writable_schema=1;
+
+UPDATE sqlite_master
+SET sql = replace(sql, 'user_id INTEGER REFERENCES users ON DELETE CASCADE', 'user_id INTEGER REFERENCES users')
+WHERE name = 'chat_tags' AND type = 'table';
+
+PRAGMA writable_schema=0;
+|]

src/Simplex/Chat/Store/SQLite/Migrations/chat_query_plans.txt

@@ -3329,6 +3329,16 @@ Query:
 Plan:
 SEARCH chat_item_versions USING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 
+Query: 
+        SELECT chat_tag_id, chat_tag_emoji, chat_tag_text
+        FROM chat_tags
+        WHERE user_id = ?
+        ORDER BY tag_order
+      
+Plan:
+SEARCH chat_tags USING INDEX idx_chat_tags_user_id (user_id=?)
+USE TEMP B-TREE FOR ORDER BY
+
 Query: 
         SELECT command_id, connection_id, command_function, command_status
         FROM commands
@@ -4333,6 +4343,20 @@ Query:
     
 Plan:
 
+Query: 
+      INSERT INTO chat_tags (user_id, chat_tag_emoji, chat_tag_text, tag_order)
+      VALUES (?,?,?, COALESCE((SELECT MAX(tag_order) + 1 FROM chat_tags WHERE user_id = ?), 1))
+    
+Plan:
+SCALAR SUBQUERY 1
+SEARCH chat_tags USING INDEX idx_chat_tags_user_id (user_id=?)
+
+Query: 
+      INSERT INTO chat_tags_chats (contact_id, chat_tag_id)
+      VALUES (?,?)
+    
+Plan:
+
 Query: 
       INSERT INTO commands (connection_id, command_function, command_status, user_id, created_at, updated_at)
       VALUES (?,?,?,?,?,?)

src/Simplex/Chat/Store/SQLite/Migrations/chat_schema.sql

@@ -663,7 +663,7 @@ CREATE TABLE operator_usage_conditions(
 );
 CREATE TABLE chat_tags(
   chat_tag_id INTEGER PRIMARY KEY AUTOINCREMENT,
-  user_id INTEGER REFERENCES users,
+  user_id INTEGER REFERENCES users ON DELETE CASCADE,
   chat_tag_text TEXT NOT NULL,
   chat_tag_emoji TEXT,
   tag_order INTEGER NOT NULL