feat: add express server and update middleware utility functions

Author: cyber-hari

README.md

@@ -557,7 +557,8 @@ A set of helpers for working with JavaScript objects, including deep merging, fl
 - `isObjEmpty(obj: Record<any, any>): boolean` – Check if an object has no own properties.
 - `pick<T, K extends keyof T>(obj: T, keys: K[]): Pick<T, K>` – Create a new object with only the specified keys.
 - `omit<T, K extends keyof T>(obj: T, keys: K[]): Omit<T, K>` – Create a new object without the specified keys.
-- `deepObjMerge<T>(target: T, source: Partial<T>): T` – Deeply merge two objects.
+- `deepObjMerge<T extends object>(target: T, ...sources: any[]): T` – Deeply merge multiple objects into the target.
+- `isPlainObject(value: any): value is Record<string, any>` – Check if a value is a plain object.
 - `flattenObject<T>(obj: T, prefix?: string): Record<string, any>` – Flatten a nested object into dot notation.
 - `getValueByPath<T>(obj: T, path: string): any` – Get a value from an object by dot path.
 - `setValueByPath<T>(obj: T, path: string, value: any): T` – Set a value in an object by dot path.