Intellishell

Added:

- Interactive [grep](https://www.gnu.org/software/grep). Performs a filtered search based on the output of the last command executed when the character is used at the beginning of the input line. This can be used as an alternative to grep, which needs to be called every time the text in the filter query changes, or if you have previously used a soft terminal search but the output may have gone beyond it.
- Use two ! characters at the end of a line and call it to get extended prompts with command comments or a brief syntax example.

Added integration with cheat.sh. Automatically search for executable commands with ! or output cheat codes for the last command entered in the line.

Added:

- Support for processing and passing variables (static and require execution) in external executable processes
- Support for automatic path completion for copy and move commands.

Fixed:

- Fixed history filtering. History output is now based on the most recently executed commands.
- Fixed problem with output of not all files and directories due to case.

Implemented:

- [x] History filtering with duplicates excluded and running the selected command (using the `Enter` button) from a drop-down list in an *external process* with support for recording executed commands in the history;
- [x] Navigate through directories with `cd` and output files for reading via `cat`, `nano`, `vim` and `mcedit`;
- [x] Captures and displays the execution time of the last executed command in the spirit of `oh-my-bash`;
- [X] Refreshing the history by using `backspace` keys and selecting a command with the `right` arrow without executing it, which is also convenient for moving to the next directory to quickly display its contents;.
- [X] Support for regular expressions during filtering, taking into account the position of entered phrases in the command using the `^` character at the beginning or end of a line (by default, the search is performed regardless of the position of entered phrases separated by a space);
- [X] Search for executable commands using the `!`.