db fix and new update request

internal/database/migrate.go

@@ -1,10 +1,13 @@
 package database
 
-import "fmt"
+import (
+	"database/sql"
+	"fmt"
+)
 
 // Migrate runs the schema bootstrap. SQLite doesn't need a migration tool —
 // CREATE TABLE IF NOT EXISTS is idempotent so this is safe to call on every start.
-func Migrate(db *DB) error {
+func Migrate(db *sql.DB) error {
 	stmts := []string{
 		`CREATE TABLE IF NOT EXISTS departments (
 			id          INTEGER PRIMARY KEY AUTOINCREMENT,