Initial commit: two-pane text redaction GUI

Rust/egui app with Nord theme and embedded Brass Mono font.
Left pane for editable source text, right pane shows redacted preview.
Select text and Ctrl+R to toggle redaction (whitespace preserved).
Ctrl+Q to quit, copy-redacted button for clipboard export.
Includes Nix flake devshell and direnv integration.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitignore

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+/target
+/.direnv