Graduate crash-drill script, fix test snapshot-sequence pinning

[WilfordGrimley]

Description

Two owner-ordered hygiene items, bundled as one small PR:

1. Graduate the crash drill. Copies crash_drill.sh (v5, byte-identical) from the orchestration repo into this repo at scripts/ops/crash_drill.sh — it passed in production 2026-07-23 (kill at 105/1000 committed, DRILL-PASS 2026-07-23T18:31:39Z). Documents it in docs/features/catalog-completion-plan.md's Stage E resume-contract section: the acceptance test now exists as a re-runnable script, and its one edit-point per run is the seeded cohort query. Refs Stage E: streaming assembly + resume contract + kill-test #153 (the drill-slice comment/close on that issue is not part of this PR — orchestrator handles issue state).

2. Conftest hoist → sequence-pinning fix. The _preserve_shared_factory_sequences capture/restore convention (forgotten twice today, breaking test_views.py snapshots both times) turned out to protect the wrong side: test_views.py is the only module in the suite whose snapshots (__snapshots__/test_views.ambr) embed a factory_boy sequence-derived value (an autogenerated "Artist N" name, reached via brainstorm_canonical_card's default CanonicalCardFactory/CanonicalArtistFactory SubFactory chain). Every other module using the same shared factories had to independently capture/restore its own use of them around itself so test_views.py's hardcoded values stayed put — fragile, and forgotten 3 times now (see docs/troubleshooting.md's retired entry for the history).

   Fix: push the pin to the one module that actually needs it. test_views.py now resets its shared factories to a fixed baseline (Factory.reset_sequence(0, force=True)) before every one of its own tests, via a new _pin_shared_factory_sequences autouse fixture — self-determined regardless of suite composition, collection order, or how many other tests ran first. Removed the now-redundant per-module _preserve_shared_factory_sequences fixture + _SHARED_FACTORIES list (and the now-unused cardpicker.tests.factories imports it required) from the other 31 test files that carried it, including test_views.py's own old request.node.name-gated single-test-insulation variant, which is no longer needed.

   docs/troubleshooting.md and docs/lessons.md rewritten in place to describe the new pattern (old entries kept as history, marked RETIRED). Added a Backend-table row + detail note to docs/upstreaming/extractable-primitives.md and a Tier-1 ladder entry to docs/upstreaming/readiness-audit.md for the pattern itself (zero fork-only imports, applicable to any factory_boy + snapshot-testing pairing) — per the docs' own upstreaming-ledger convention, judged honestly: it's a pattern-level primitive, not a file to lift (its current call site, test_views.py, asserts real fork-only fields elsewhere in the same file).

Checklist

• I have installed pre-commit and installed the hooks with pre-commit install before creating any commits. (pre-commit run --files <all touched> clean: ruff, isort, black, mypy, prettier all pass)
• I have updated any related tests for code I modified or added new tests where appropriate. (test-infra-only change; test_views.ambr re-recorded via --snapshot-update, diff confirmed purely additive — the 6 changed keys are exactly the sequence-derived "Artist N" → "Artist 0" values, nothing else)
• I have manually tested my changes as follows:
  • Full backend suite (pytest . from MPCAutofill/, real Postgres/Elasticsearch via testcontainers on the host venv): 1829 passed, 4 skipped, 0 failed (verified twice, before and after the pre-commit auto-fix pass)
  • Verified pytest cardpicker/tests/test_views.py --snapshot-update in isolation now produces byte-identical output to the full-suite --snapshot-update run (the old single-file-vs-full-suite divergence this fix retires)
  • diff-verified scripts/ops/crash_drill.sh is byte-identical to the orchestration repo's already-passed v5 copy
• I have updated any relevant documentation or created new documentation where appropriate. (catalog-completion-plan.md, troubleshooting.md, lessons.md, extractable-primitives.md, readiness-audit.md — all edited in place, no new files)

Closes nothing; refs #153.