Execute the public guide and explain code samples in docs-local #1554

Problem

No test runs the code samples in the public guides or the SDL explainer, so samples that no longer work go unnoticed. The docs lane (nox -s docs-local) runs "docs / executable quickstart" (tools/nox_support/test_lanes.py:305-318 on dev a4357f9a), which runs only the three tests in PUBLIC_DOCS_EXAMPLE_TESTS (tools/nox_support/config.py:21-25): the checked-in quickstart scenario, the README quickstart, and the participant-control claim example.

Two broken samples on dev a4357f9a show the gap:

• docs/public/guides/python.md:35-52 renames nodes.web to frontend in first-scenario.sdl.yaml, the file the guide's first example loads. The rename returns succeeded=False with artifact-transformation.target-invalid (docs(guides): correct the imports, rename and CLI-reference statements in the CLI and Python guides #1492, which replaces the example).
• The Quick Example in docs/explain/sdl/index.md (lines 97-147), where docs/explain/getting-started.md:64 sends new authors, uses vulnerabilities on a node (:111) and as a top-level block (:129). Replace domain-shaped SDL classification fields with generic concept bindings #989 removed both forms from canonical SDL, and the example fails raes semantic validate - with sdl.classification-migration-required (docs(sdl): make the SDL reference example valid and fix two stale statements #1493, which fixes it).

Scope

• Run the samples in docs/public/guides/ and the SDL samples in docs/explain/ from the docs lane: validate complete SDL scenarios, execute Python samples, and run offline CLI samples, checking the documented outcome.
• Mark fragments and intentionally invalid samples explicitly so the runner skips or inverts them with a reason.

Done when

• nox -s docs-local validates every complete SDL sample in docs/public and docs/explain and runs every Python and offline CLI sample in docs/public/guides.
• Restoring the old python.md rename example or the old Quick Example makes nox -s docs-local fail.
• Fragments and intentionally invalid samples are marked, and the runner reports why each is skipped.

Related

• docs(guides): correct the imports, rename and CLI-reference statements in the CLI and Python guides #1492, docs(sdl): make the SDL reference example valid and fix two stale statements #1493 (noted it)
• Replace domain-shaped SDL classification fields with generic concept bindings #989 (classification migration), Renaming a node refuses instead of renaming its infrastructure entry #1550 (the node-rename limit)