fix(plans): switch B7 burn-in to burnin-dummy repo

nsis-plugin-ns7zip is a real C++ project — wrong for lifecycle testing.
burnin-dummy simulates ~30s work and writes to dist/ with no external
deps. Documents one-time prerequisites (group, keyring, Gitea push).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plans/PhaseB-user-checklist.md

@@ -452,6 +452,25 @@ coesistono mai.
 baseline Windows (entro ±20%). I due burn-in sono sequenziali
 (dual-boot: un OS alla volta).
 
+  > **Prerequisiti una-tantum** (come `simone`):
+  > ```bash
+  > sudo usermod -a -G ci-runner simone
+  > sudo chmod g+w /var/lib/ci/artifacts/ /var/lib/ci/build-vms/
+  > mkdir -p ~/.local/share/python_keyring
+  > sudo cp /home/ci-runner/.local/share/python_keyring/keyring_pass.cfg \
+  >     ~/.local/share/python_keyring/
+  > sudo chown simone: ~/.local/share/python_keyring/keyring_pass.cfg
+  > chmod 600 ~/.local/share/python_keyring/keyring_pass.cfg
+  > ```
+  > Il repo `burnin-dummy` deve esistere in Gitea (`Simone/burnin-dummy`).
+  > Push iniziale (una-tantum):
+  > ```bash
+  > cd /opt/ci/local-ci-cd-system/gitea/burnin-dummy
+  > git init && git add . && git commit -m "initial"
+  > git remote add origin http://10.10.20.11:3100/Simone/burnin-dummy.git
+  > git push -u origin main
+  > ```
+
 - [ ] **Avviato in Linux** — burn-in 4 job concorrenti × 10 round su
       `WinBuild2025`:
 
@@ -459,29 +478,25 @@ baseline Windows (entro ±20%). I due burn-in sono sequenziali
   pwsh /opt/ci/local-ci-cd-system/scripts/Test-CapacityBurnIn.ps1 \
     -Parallelism 4 -Rounds 10 \
     -TemplatePath /var/lib/ci/templates/WinBuild2025/WinBuild2025.vmx \
-    -RepoUrl 'http://10.10.20.11:3100/Simone/nsis-plugin-ns7zip.git' \
+    -RepoUrl 'http://10.10.20.11:3100/Simone/burnin-dummy.git' \
     -CloneBaseDir /var/lib/ci/build-vms/ \
     -ArtifactBaseDir /var/lib/ci/artifacts/ \
     -VmrunPath /usr/bin/vmrun \
-    -BuildCommand 'New-Item -ItemType Directory -Force dist | Out-Null; Set-Content -Path dist\build-info.txt -Value build-ok'
+    -BuildCommand 'powershell -ExecutionPolicy Bypass -File .\build.ps1'
   ```
 
-  > **Prerequisiti** (una-tantum, come `simone`):
-  > `sudo usermod -a -G ci-runner simone && sudo chmod g+w /var/lib/ci/artifacts/ /var/lib/ci/build-vms/`
-  > Poi copia il keyring: `mkdir -p ~/.local/share/python_keyring && sudo cp /home/ci-runner/.local/share/python_keyring/keyring_pass.cfg ~/.local/share/python_keyring/ && sudo chown simone: ~/.local/share/python_keyring/keyring_pass.cfg && chmod 600 ~/.local/share/python_keyring/keyring_pass.cfg`
-
 - [ ] **Avviato in Linux** — burn-in 4 × 10 su `LinuxBuild2404`:
 
   ```bash
   pwsh /opt/ci/local-ci-cd-system/scripts/Test-CapacityBurnIn.ps1 \
     -Parallelism 4 -Rounds 10 \
     -TemplatePath /var/lib/ci/templates/LinuxBuild2404/LinuxBuild2404.vmx \
-    -RepoUrl 'http://10.10.20.11:3100/Simone/nsis-plugin-ns7zip.git' \
+    -RepoUrl 'http://10.10.20.11:3100/Simone/burnin-dummy.git' \
     -CloneBaseDir /var/lib/ci/build-vms/ \
     -ArtifactBaseDir /var/lib/ci/artifacts/ \
     -VmrunPath /usr/bin/vmrun \
     -GuestOS Linux \
-    -BuildCommand 'mkdir -p dist && echo build-ok > dist/build-info.txt'
+    -BuildCommand 'bash build.sh'
   ```
 - [ ] Misurare:
   - [ ] Tempo medio per job, confronto con baseline A5