[containers] Update local-dev.mdx

[zach-is-my-name]

Main Changes:

1. Added "Required Configuration" section - Shows the complete wrangler.json structure needed for local development
2. Clarified required fields:
   - name field in container config
   - instance_type field (typically "standard")
   - nodejs_compat compatibility flag
3. Added troubleshooting note - Explains that missing these fields causes "Connection refused" errors
4. Removed misleading phrase - Changed "without additional configuration" to just describing how to run the commands

The updated documentation now accurately reflects what's actually needed to get containers working locally,
preventing the issues we encountered. This should help other developers avoid the debugging session we just
went through!

Credit to https://github.com/megaconfidence/wifski/tree/main for providing the correct pattern.

Summary

Screenshots (optional)

Documentation checklist

• Is there a changelog entry (guidelines)? If you don't add one for something awesome and new (however small) — how will our customers find out? Changelogs are automatically posted to RSS feeds, the Discord, and X.
• The documentation style guide has been adhered to.
• If a larger change - such as adding a new page- an issue has been opened in relation to any incorrect or out of date information that this PR fixes.
• Files which have changed name or location have been allocated redirects.

[emily-shen]

instance_type and name, and the node_compat flag aren't required in local dev (or production) - i've just tested it out without those fields, and not had any issues. maybe you're hitting a bug? D: are you able to create a repro and open an issue in workers-sdk?

[zach-is-my-name]

I’d you can’t reproduce please close it. I can’t chase it down if I made a bad report. Sorry

…

On Thu, Aug 21, 2025 at 11:56 AM emily-shen ***@***.***> wrote: ***@***.**** requested changes on this pull request. instance_type and name, and the node_compat flag aren't be required in local dev - i've just tested it out without those fields, and not had any issues. maybe you're hitting a bug? D: are you able to create a repro and open an issue in workers-sdk? — Reply to this email directly, view it on GitHub <#24598 (review)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AD2RU5GDOLP3ZSN64GU4UC33OXT2FAVCNFSM6AAAAACEOX2SJGVHI2DSMVQWIX3LMV43YUDVNRWFEZLROVSXG5CSMV3GSZLXHMZTCNBRGMZDGNZZGE> . You are receiving this because you authored the thread.Message ID: ***@***.***>