fix(tests): redirect stdin from /dev/null in uninstall test to prevent hang

--uninstall prompts for config removal when stdin is a TTY. Running the
test from an interactive terminal caused it to block on read. Feeding
/dev/null forces the non-interactive path without changing behaviour.

tests/run_tests.sh

@@ -259,7 +259,7 @@ fi
 
 # 16. Uninstall — removes installed files, config is kept in non-interactive mode
 it "uninstalls installed files (keeps config)"
-uninstall_out=$("$COLOR_TOOL" --uninstall 2>&1)
+uninstall_out=$("$COLOR_TOOL" --uninstall </dev/null 2>&1)
 if [[ ! -e "$HOME/.local/bin/color-tool" ]] &&
    [[ ! -L "$HOME/.local/bin/color-tool" ]] &&
    [[ ! -d "$XDG_DATA_HOME/color-tool" ]] &&