Refactor task usage and profile auto update

Library/Database/Databse.swift

@@ -1,7 +1,7 @@
 import Foundation
 import GRDB
 
-class Database {
+actor Database {
     private static var writer: (any DatabaseWriter)?
 
     static func sharedWriter() throws -> any DatabaseWriter {
@@ -11,8 +11,6 @@ class Database {
         try FileManager.default.createDirectory(at: FilePath.sharedDirectory, withIntermediateDirectories: true)
         let database = try DatabasePool(path: FilePath.sharedDirectory.appendingPathComponent("settings.db").relativePath)
         var migrator = DatabaseMigrator().disablingDeferredForeignKeyChecks()
-        migrator.eraseDatabaseOnSchemaChange = true
-
         migrator.registerMigration("initialize") { db in
             try db.create(table: "profiles") { t in
                 t.autoIncrementedPrimaryKey("id")
@@ -29,6 +27,11 @@ class Database {
                 t.column("data", .blob)
             }
         }
+        migrator.registerMigration("add_auto_update_interval") { db in
+            try db.alter(table: "profiles") { t in
+                t.add(column: "autoUpdateInterval", .integer).notNull().defaults(to: 0)
+            }
+        }
 
         try migrator.migrate(database)
         writer = database