Fix TUI newline display issue

- Add processEscapeSequences() function to convert literal \n to actual newlines
- Apply fix to backup success, error, and running output displays
- Add TUI binary to gitignore
- Include comprehensive documentation of the fix

Resolves issue where backup output showed literal escape sequences
instead of properly formatted text with line breaks.

.gitignore

@@ -38,3 +38,6 @@ immich/b2-linux
 
 # Generated dotfiles - these are created dynamically by bootstrap process
 dotfiles/my-aliases.zsh
+
+# Compiled binaries
+tui/tui