How many GitHub projects have merged the pull requests

Nowadays, GitHub supports archiving repositories.

Archiving repositories

You can archive a repository to make it read-only for all users and indicate that it's no longer actively maintained. You can also unarchive repositories that have been archived.
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1. On GitHub, navigate to the main page of the repository.

2. Under your repository name, click ⚙ Settings.

   

3. Under "Danger Zone", click Archive this repository or Unarchive this repository.

   

4. Read the warnings.

5. Type the name of the repository you want to archive or unarchive.

   

6. Click I understand the consequences, archive this repository.

Read more at GitHub help on Archiving a GitHub repository

There is no way to do this without the command line. GitHub does not have a way to promote gists into a repo.

While the GitHub interface does allow you to edit files in your repository, they have to already be there via a git push from your local.

Should they add the ability to add files via the web interface then you would be able to "promote" a gist into a GitHub repo via a standard copy and paste of its contents. But that would also not carry over any of the gist's history of commits.

If you still want to, you'll have to use the command line or IDE.

1. Head to your gist and look for the Public/Private Clone URL

2. Click it.

   You'll see a pop up with info such as this:

   Use this clone URL yourself.
   git clone git@gist.github.com:{SHA-1}.git local-repo

3. Run the git clone to your local

   You may be required to confirm the download if the authenticity of the host, gist.github.com, cannot be established.

   You may also have to enter your passphrase to connect to GitHub

4. Update the remote to your GitHub repo, of where you want to push these files.

   git remote set-url origin {git://new.url.here}
   

Now you should be able to push the gist files into a GitHub repo, with all their commit revision history.