feat: run the PR checks with one command

scripts/generate_readme.py

@@ -42,6 +42,7 @@ import release_record
 from siteguides import install_command
 from validate_pr import LARGE_FILE_ISSUE_URL
 from largefiles import load_registered_paths
+import pr_checks
 from verify import verify_platform
 
 
@@ -939,6 +940,8 @@ def contributing_text(
     .md for the site); *site_words* names the site from where the text is read.
     """
     pip_line, floor_line = ci_install_lines()
+    width = max(len(step.command) for step in pr_checks.STEPS)
+    steps = "\n".join(f"{step.command:<{width}}  # {step.why}" for step in pr_checks.STEPS)
     return f"""{title}
 
 ## Add a BIOS file
@@ -1014,17 +1017,14 @@ the checks CI runs on a pull request (Python 3.12 or newer):
 
 ```bash
 {pip_line}
-python scripts/validate_pr.py --changed          # the BIOS files the branch adds
-python scripts/validate_schemas.py --source-only # profiles and platform files
-python scripts/profile_sync.py --added --strict  # each profile the branch adds
-python scripts/export_native.py --all --fetch --output-dir tmp/native  # files the exporter tests compare with
-python scripts/refresh_data_dirs.py  # data directories the pack-building tests read
-python scripts/generate_site.py       # the pages the site tests read
-npm ci --prefix website && npm run build --prefix website  # the built site, Node 24
-python -m unittest discover -s tests -t .
-python scripts/validate_site.py --site-dir website/dist  # links and page budgets
-vermin --no-tips -t=3.8- --violations install.py         # install.py stays on Python 3.8
-python3.8 -m unittest tests.test_install_tui  # the full screen on the installer's floor
+python scripts/pr_checks.py
+```
+
+`pr_checks.py` runs these, in CI's order, carries on past a failure as CI
+does, and names at the end each check that failed or could not run:
+
+```bash
+{steps}
 ```
 
 The versions are the ones CI pins. Three tools come from the system, not from