docs: replace prose placeholders in reproduction steps with executable commands

The audit found ~80 placeholders, and the damaging ones were where the
measuring apparatus itself was prose rather than a command:

  a6  "( curl ... ) & 를 20개 띄우고 wait"  — the 22.2s headline came from this
  a3  "<로그인 반복, sid 를 /tmp/sids 에>"  — the whole RPO measurement
  a3  "<sid 목록>"                          — the control it is compared against
  a5  "<수신 파드IP>"                       — the injection
  a8  writes /tmp/tok, reads /tmp/rt        — self-inconsistent, sent an empty token
  b3  $KC / $RT / $NEW never assigned
  c2  bare kcadm.sh with no kubectl exec
  a1  conntrack tuples written by hand, though the direction flips per restart

Each is now a shell-expandable form: pod IPs from jsonpath, the admin password
from the secret, ids from kcadm --format csv, conntrack tuples derived from
"conntrack -L" with awk rather than transcribed.

Then the rewritten commands were executed against the live cluster, and one
of them failed — the 20-way load generator, written as "kubectl run --rm -i",
lost its output stream twice in a row. That is a trap this series already hit
once, and the rewrite reintroduced it. A-6 now uses a resident probe pod that
collects into a file and is cat-ed once; verified 20/20 lines.

Evidence: docs/evidence/followup/05-command-reproducibility.txt

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/experiment-a4-node-loss.md

@@ -404,7 +404,7 @@ kubectl get node kc-lab-2                        # 40초 뒤 NotReady
 kubectl -n keycloak-lab get pods -o wide         # Running 인 채로 얼어 있다
 kubectl get node kc-lab-2 -o jsonpath='{.spec.taints}'
 #   5분 뒤 Terminating + 새 파드 Pending
-kubectl -n keycloak-lab describe pod <new-pod> | grep -A4 Events
+kubectl -n keycloak-lab describe pod $(kubectl -n keycloak-lab get pods -l app=postgres --field-selector=status.phase=Pending -o jsonpath='{.items[0].metadata.name}') | grep -A4 Events
 
 # 4b 컨트롤 플레인 상실 — kubectl 이 죽으므로 노드에서 직접 본다
 virsh destroy kc-lab-1