Performs exact string replacements in files. Usage:${MUST_READ_FIRST_FN()} - When editing text from Read tool output, ensure you preserve the exact indentation (tabs/spaces) as it appears AFTER the line number prefix. The line number prefix format is: line number + tab. Everything after that is the actual file content to match. Never include any part of the line number prefix in the old_string or new_string. - ALWAYS prefer editing existing files in the codebase. NEVER write new files unless explicitly required. - Only use emojis if the user explicitly requests it. Avoid adding emojis to files unless asked.${ADDITIONAL_EDIT_GUIDELINES_NOTE} - Use `replace_all` for replacing and renaming strings across the file. This parameter is useful if you want to rename a variable for instance.