Added Sanitization for the input file for termux-open command

[eternalfrustation]

The termux-open command had no sanitization for the input file, which prevented it from opening files containing % characters, this P.R. adds that sanitization.

termux/termux-app/#3250

[agnostic-apollo]

If you always do encoding, you will break paths if they were already encoded by user before passing to termux-open, so you need to add an -e and --encode option that conditionally does it.

Moreover, it's best not to encode yourself, encoding algorithms are very complex. You can use curl to encode. Add following after if [ -f "$FILE" ] condition.

if [ "$ENCODE" = "1" ]; then
    # Encode FILE with curl. sed replaced trailing newline and the "/?" prefix.
    # - https://stackoverflow.com/a/10797966
    FILE="$(printf "%s" "$FILE" | { curl -Gs -w %{url_effective} --data-urlencode @- ./ || :; } | sed -e "s/%0[aA]$//; s/^[^?]*?\(.*\)/\1/")"
fi

Also commit format must be as per repo git history. Use

termux-open: Add `-e` and `--encode` options to encode characters like `%` in file path

Closes termux/termux-app#3250