test: raise smoke pod memory floor

[chimerakang]

Summary

• raise Alpine smoke and e2e Pod memory requests/limits to 256Mi
• matches apple/container's observed minimum VM memory requirement during local kind smoke testing

Validation

• go test ./...
• golangci-lint run
• make build
• kind-backed single-node smoke: macvz-local registered Ready; alpine-smoke reached Running/Ready; runtime VM ran arm64; delete cleaned up VM
• kubelet HTTPS smoke: kubectl logs, exec, stats/summary, and metrics/resource succeeded with a cluster-CA-signed serving cert

[chimerakang]

Closing for now; keeping the smoke memory-floor fix local while continuing local validation.