Invisible Text Generator

Replace every Unicode character in the input except line breaks with one U+200B ZERO WIDTH SPACE, preserving newline positions. The preview intentionally shows only a count such as `[12 invisible characters — use Copy]`, while the copy button receives the actual zero-width sequence. This is replacement, not visual hiding or encryption: original letters cannot be recovered from the output, and different inputs with the same code-point count produce the same invisible text. Apps may strip, normalize, reveal, reject, or moderate zero-width characters, and they can affect searching and cursor movement. Generation is local; use it only where hidden characters are permitted and never to bypass platform rules.