Investigate e2e test failures

[pfeifferj]

using this issue to collect some findings. this issue should later be split into multiple:

TestE2ETaintSync Failures

 nodeclaims.karpenter.sh "test-nodepool-taint-sync-...-cwjfm" not found
 Test: TestE2ETaintSync
 Messages: Node should be created
 --- FAIL: TestE2ETaintSync (370.97s)
 FAIL

but then the wrapper script reports "Test TestE2ETaintSync passed" (false positive due to script logic checking exit code incorrectly)

---

Pre-test warnings show leftover resources from previous runs:

 Warning: Found 1 NodeClaim resources before test start
   - test-kubelet-config-pool-h25kj (Conditions: 7)

The cleanup step uses invalid kubectl patch syntax:

 kubectl patch nodeclaims --selector test=e2e --type='merge' ...
 error: unknown flag: --selector

This prevents proper cleanup of stuck resources.

[pfeifferj]

/assign