SSH clone URL support
Buttons now work when the GitHub clone picker is set to SSH (previously only HTTPS was recognised).

Dynamic URL resolution
Repo URL is resolved at click time, so switching between HTTPS/SSH after buttons appear is handled correctly.

IDE validation
Stored IDE ID is now validated against the supported list; invalid values fall back to idea.

Async/await refactor
getDefaultIDE rewritten for cleaner error handling and a more reliable localStorage fallback.