Validate normalized palindromes with variants

Implement a function isNormalizedPalindrome(s) that returns true if s reads the same forward and backward after removing non‑alphanumeric characters and case‑folding. Follow‑ups: ( 1) Support full Unicode normalization (e.g., NFKD), diacritics stripping, and locale‑specific case rules. ( 2) Handle a streaming input where s may not fit in memory; optimize for one pass and sublinear extra space. ( 3) Allow at most one character deletion to still count as a palindrome; generalize to up to k deletions. ( 4) Return the index pair of the first mismatch if not a palindrome. Discuss time/space complexity, edge cases, and unit tests.