fix: improve command argument handling in ExecuteCommand function

[teemow]

This pull request updates the ExecuteCommand method in the internal/teleport/client.go file to improve how command arguments are handled. The key change is the introduction of logic to split the command string into individual arguments before appending additional arguments.

Improvements to command argument handling:

• internal/teleport/client.go: Updated the ExecuteCommand method to split the command string into individual arguments using strings.Fields, ensuring better handling of multi-word commands. This replaces the previous approach where the command string was treated as a single argument.