feat(contrib): add background_interval plugin

[jcpunk]

Description

• Adds a plugin for setting up background scheduled functions

Closes

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 67.43%. Comparing base (1d63bd0) to head (3b69a98).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4660      +/-   ##
==========================================
+ Coverage   67.32%   67.43%   +0.10%     
==========================================
  Files         292      293       +1     
  Lines       14933    14982      +49     
  Branches     1673     1675       +2     
==========================================
+ Hits        10054    10103      +49     
  Misses       4743     4743              
  Partials      136      136              

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[jcpunk]

My specific use case is for pruning data for GDPR. My application can set lifecycles for automatic expiration as well as manual cleanups.

This type of background task scheduling is something I thought might be of wider value.

[provinzkraut]

Thank you for the contribution, but this is somewhat outside the scope of Litestar itself. If you want to publish this, I'd recommend you do it as an independent project.