chore(backport release-1.0): fix: sharded Warehouse cross-controller access

[akuitybot]

Automated backport to release-1.0, triggered by a label in #2819.

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 10 lines in your changes missing coverage. Please review.

Project coverage is 48.82%. Comparing base (63ce8a5) to head (638c52a).
Report is 1 commits behind head on release-1.0.

Files with missing lines	Patch %	Lines
cmd/controlplane/controller.go	0.00%	6 Missing ⚠️
internal/controller/warehouses/warehouses.go	0.00%	4 Missing ⚠️

Additional details and impacted files

@@               Coverage Diff               @@
##           release-1.0    #2820      +/-   ##
===============================================
- Coverage        48.84%   48.82%   -0.02%     
===============================================
  Files              270      270              
  Lines            23934    23941       +7     
===============================================
  Hits             11690    11690              
- Misses           11613    11620       +7     
  Partials           631      631              

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