feat: update 'create' cmd section to 'Agentic AI app'

[mwbrooks]

Summary

This pull request updates the slack create command's section from "AI app" to "Agentic AI app" to align with Slack's AI branding and the industry's general direction.

Preview

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 64.87%. Comparing base (b724d81) to head (258d3f8).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #293   +/-   ##
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  Coverage   64.87%   64.87%           
=======================================
  Files         213      213           
  Lines       17550    17550           
=======================================
  Hits        11385    11385           
  Misses       5101     5101           
  Partials     1064     1064           

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[zimeg]

@mwbrooks LGTM and thanks for keeping us withe the latest 👾 ✨

It's interesting to find that changes to available template strings were all that's needed for this change, but testing still finds the right templates for me!

I do wonder if we should follow up with renaming templates from "bolt-js-assistant-template" to "bolt-js-agent-template" but we can save this discussion for later of course 🚢

[zimeg]

Suggested change

	Title: fmt.Sprintf("Agentic AI app %s %s", style.Secondary("Slack agents and assistants"), style.Emoji("sparkles")),
	Title: fmt.Sprintf("Agentic AI app %s", style.Secondary("Slack agents and assistants")),

suggestion(non-blocking): This highlights interesting features but I wonder if moving this to be the second option suffices? The emoji logic might otherwise output strange characters for Windows machines at this time...