Write a function in Typescript that uses generics to return the first non-repetitive character in a string. If no nonrepetitive char is found it should return a null. Please handle edge conditions - input and output. // Example usage: const result = firstNonRepeatingCharacter("aabbccddeeffg"); console.log("First non-repeating character:", result); // Output: "g" const result = firstNonRepeatingCharacter("abcabc"); console.log("First non-repeating character:", result); // Output: null