Hostinger Reach integration UI + ARC Buildium matching, drop Mailchimp

- HostingerReachPage (replaces MailchimpPage): connect Reach via
  reach-connection, per-association segment sync via reach-sync
- ARC Applications: Buildium import review/matching updates
- buildium-import-stage/apply: latest staging + apply changes (already
  deployed to Supabase)
- migrations: hostinger_reach_integration + arc_finalized_lock service
  role (already applied to live DB)
- CI: note that deployment is VPS-side polling (auto-deploy.sh cron)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -26,23 +26,8 @@ jobs:
       - name: Build
         run: bun run build
 
-  deploy:
-    # Auto-deploy to the VPS (avria.cloud) on every push to main.
-    # The SSH key is restricted on the server (forced command): it can only
-    # run /home/avria/deploy.sh, which pulls main, builds, and rsyncs
-    # dist/ -> public_html. The command string below is therefore ignored
-    # by the server but kept descriptive.
-    needs: build
-    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
-    runs-on: ubuntu-latest
-    steps:
-      - name: Deploy to VPS
-        run: |
-          mkdir -p ~/.ssh
-          printf '%s\n' "$VPS_DEPLOY_KEY" > ~/.ssh/deploy_key
-          chmod 600 ~/.ssh/deploy_key
-          printf '%s\n' "$VPS_HOST_KEY" > ~/.ssh/known_hosts
-          ssh -i ~/.ssh/deploy_key -o IdentitiesOnly=yes avria@2.25.155.250 "deploy main"
-        env:
-          VPS_DEPLOY_KEY: ${{ secrets.VPS_DEPLOY_KEY }}
-          VPS_HOST_KEY: ${{ secrets.VPS_HOST_KEY }}
+# Deployment: the VPS (avria.cloud) polls this repo every 2 minutes via
+# /home/avria/auto-deploy.sh (cron, user avria) and runs deploy.sh when main
+# moves — pull/build/rsync to public_html. CI here is a build check only;
+# pushing SSH from Actions doesn't work because Hostinger's edge firewall
+# blocks the runners' IPs.