Add database migrations for workspace background feature

- Add migration 0001 for background column in haex_workspaces table
- Update vault.db with new schema
- Sync Android assets database

src-tauri/database/migrations/0001_furry_brother_voodoo.sql

@@ -0,0 +1,15 @@
+PRAGMA foreign_keys=OFF;--> statement-breakpoint
+CREATE TABLE `__new_haex_workspaces` (
+	`id` text PRIMARY KEY NOT NULL,
+	`device_id` text NOT NULL,
+	`name` text NOT NULL,
+	`position` integer DEFAULT 0 NOT NULL,
+	`background` text,
+	`haex_timestamp` text
+);
+--> statement-breakpoint
+INSERT INTO `__new_haex_workspaces`("id", "device_id", "name", "position", "background", "haex_timestamp") SELECT "id", "device_id", "name", "position", "background", "haex_timestamp" FROM `haex_workspaces`;--> statement-breakpoint
+DROP TABLE `haex_workspaces`;--> statement-breakpoint
+ALTER TABLE `__new_haex_workspaces` RENAME TO `haex_workspaces`;--> statement-breakpoint
+PRAGMA foreign_keys=ON;--> statement-breakpoint
+CREATE UNIQUE INDEX `haex_workspaces_position_unique` ON `haex_workspaces` (`position`);