bun-{create,c}: add page

[AttackThwarter]

Checklist

Hi! This PR addresses the 2 part of Issue #19127 .

• The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• The page description(s) have links to documentation or a homepage.
• The page(s) follow the content guidelines.
• The page(s) follow the style guide.
• The PR contains at most 5 new pages.
• The PR is authored by me, or has been human-reviewed if it was created with AI or machine translation software.
• The PR title conforms to the recommended templates.
• Version of the command being documented (if known):

Reference issue: #19127

[AttackThwarter]

Hi @Managor, @TheRootDaemon, and @acuteenvy,

Thank you all so much for the detailed review and the collaborative discussion! This was incredibly helpful.

Let me know if anything else is needed!

[sebastiaanspeck]

Same comment as here: #19181 (comment)

[AttackThwarter]

Thanks @sebastiaanspeck!

Following our discussion on the other PR (#19181), I've updated this page (bun-create) to use the same 'header note' style for consistency. The change is pushed.