fix: normalize CRLF text input across text effects

[Nomadcxx]

Summary

• add normalizeMultilineText helper to normalize CRLF/CR to LF
• apply normalization in constructors and SetText for matrix-art, rain-art, ring-text, blackhole, beam-text, and print
• add regression test TestTextEffects_NormalizeCRLFInput to prevent carriage-return leakage into rendered output

Why

CRLF text files could leak raw carriage-return control characters into effect rendering and width calculations, which breaks ASCII layout (including skull/text art usage).

Verification

• go test ./animations -run TestTextEffects_NormalizeCRLFInput -v
• go test ./animations