Redirect Manager: Large-Scale Import Optimization

[YegorKozlov]

The current implementation stores redirects as direct children under the caconfig parent, creating performance issues during bulk import from Excel.

/conf/my-site/settings/redirects
  - redirect-1
  - redirect-2
  ...
  - redirect-10000

For example, importing 50K redirects from the attached sample takes approximately an hour on a standard development machine.

Proposed Solution:

Implement a sharding mechanism to optimize redirect storage and improve import performance:

/conf/my-site/settings/redirects
  + shard1
	- redirect-1
	...
	- redirect-1000
  + shard2
	- redirect-1001
	...
	- redirect-2000
  + shard3
	- redirect-2001
	...
	- redirect-3000