Issue 2: — Add to_title_case() utility function

[O-sama12]

Description

Textcraft currently supports multiple text case transformations,
but does not include a title case utility.

This issue proposes adding a to_title_case() function.

Suggested Tasks

• Implement to_title_case(text: str) -> str
• Handle extra spaces cleanly
• Add a docstring and type hints
• Update README with a small example

Why this matters

• Completes the set of common case transformations
• Beginner-friendly feature addition
• Improves usability

Difficulty

🟢 Beginner-friendly