* Implement function to prune string keeping HTML closing tags Fixes #1587 * change const name remove unneeded comment * move pruneHTML to separated file * move const back to telegram.go * Add unit tests for string array manipulation and HTML pruning Introduce comprehensive test cases for stringArr methods (Push, Pop, Unshift, Shift, String) to ensure correct behavior and state management. Additionally, add tests for HTML pruning functions (pruneHTML, pruneStringToWord) to validate handling of length constraints and formatting scenarios. * Improve behavior * Fix pruneHTML to count visible text only, add parent text pruning - Fix bug where HTML tags were counted toward the character limit instead of only visible text content - Add pruning for parent comment text in Telegram notifications - Simplify pruneStringToWord using strings.LastIndex - Remove unused stringArr type and its tests - Consolidate and simplify test cases --------- Co-authored-by: Umputun <umputun@gmail.com> Co-authored-by: Dmitry Verkhoturov <paskal.07@gmail.com>