Issue #3550141: Content outline: Title tag

Closes #3550141

Testing instructions

• Run npm run dev -w app
• Go to the Content outline tab
• Add a title
• Click the lightbulb to open generated titles
• Enter a brand
• Click the refresh button to reload the titles
• Select a title
• Verify the selected title is in the text input
• Verify the length indicator works (can't verify the topic indicator for now)