feat: add stale bot

[jleach]

Summary of Changes

This PR adds the "stale" bot to automatically close issues after they have not seen any update or progress in 1 year.

Screenshots, videos, or gifs

n/a

Breaking change guide

None

Related Issues

n/a

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud