Resolve "AI generated response sometimes includes HTML tags"

Changes made on this MR:

• Improvements on ui in general: colors, layout and elements distribution
• Prevent results from being inserted with html tags
• Input gets focused when the tool shows up.
• Custom prompts are sent by click instead of just filling the input
• New action (copy: copies the text from the current tab results to clipboard)
• New action (toggle fullscreen: ability to toggle fullScreen)
• Results can be edited (only for the 'content' tab for now)
• Results are sent along with user input.
• Selected text is appended to the content tab for editing.