chore: fix shellcheck findings across migration scripts

phase8_post_check.sh

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
 set -euo pipefail
+# shellcheck disable=SC2329
 
 # =============================================================================
 # phase8_post_check.sh — Verify Phase 8 (Cutover) succeeded
@@ -41,6 +42,7 @@ run_check "HTTPS returns 200 at https://${GITEA_DOMAIN}" \
   curl -sf -o /dev/null "https://${GITEA_DOMAIN}/api/v1/version"
 
 # Check 2: HTTP redirects to HTTPS (returns 301)
+# shellcheck disable=SC2329
 check_redirect() {
   local http_code
   http_code=$(curl -sI -o /dev/null -w "%{http_code}" "http://${GITEA_DOMAIN}/")
@@ -49,6 +51,7 @@ check_redirect() {
 run_check "HTTP → HTTPS redirect (301)" check_redirect
 
 # Check 3: SSL certificate is valid (not self-signed)
+# shellcheck disable=SC2329
 check_ssl_cert() {
   # Verify openssl can connect and the cert is issued by a recognized CA
   local issuer
@@ -66,6 +69,7 @@ done
 
 # Check 5: GitHub repos are marked as offsite backup
 for repo in "${REPOS[@]}"; do
+  # shellcheck disable=SC2329
   check_mirror_marked() {
     local desc
     desc=$(github_api GET "/repos/${GITHUB_USERNAME}/$1" | jq -r '.description // ""')