LCORE-2844: Instruct CodeRabbitAI to perform performance and algoritmic complexity checks

Author: tisnik

.coderabbit.yaml

@@ -85,7 +85,18 @@ reviews:
 
     issue_assessment:
       mode: warning
-    custom_checks: []
+    custom_checks:
+      - name: 'Performance and Algorithmic Complexity'
+        mode: error
+        instructions: |
+          BLOCKING. Flag only meaningful performance regressions:
+          1. O(n^2)+ algorithms on non-trivial inputs (handlers, K8s list operations).
+          2. N+1 patterns: list-then-query-per-item (K8s API, DB).
+          3. Expensive work inside loops (API calls, JSON parsing, regex compilation).
+          4. Unbounded growth: caches, watchers, buffers without eviction/limits.
+          5. Missing pagination/limits on List operations or API endpoints.
+
+          Per issue: file, lines, risk, fix category. If clean, mark PASSED.
 
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