Update UI button labels

[ericglau]

• Changes "Deploy with Defender" button to "Deploy", since some users may not be familiar with what Defender is.
  • Adds arrows to suggest that this button opens a modal rather than deploys immediately
  • Depends on changing the "Get API Key" label in the modal to "Get API Key from OpenZeppelin Defender" to provide more context. Update Wizard's get API key link defender-deploy-plugin#52
• Adds "Open in Remix" text to the Open in Remix button, since the icon may not be well known
• Adds "AI Assistant" text to the AI Assistant button, since the icon may not be well known
  • Resized the button to fit text
• Adjusts layer order so the Deploy modal covers the AI Assistant, since AI Assistant does not help with Deploy

[CoveMB]

Looks clean

[makiopen]

LGTM