Tooling: requirements_test.txt becomes the single source of backend CI
dependencies; pyproject.toml configures ruff (E/F/B/I, E501 excluded by
decision) and mypy strict for a grow-only allowlist of six pure modules
(junction_limits annotated to pass). The 42 substantive ruff findings
are fixed — the B023 loop-variable closures bind their variables as
parameter defaults instead of hiding behind noqa, and every remaining
noqa carries a reason (guarded by a test).
Errors: const.ERROR_CODES / ERROR_CODE_FAMILIES formalise the stable
contract; the scanner test proves every emitted code across BOTH paths
(send_error literals; class attrs, literal and variable-passed
MarkerControlError codes, f-string families) is registered and has a
localized message — 22 missing backup.error.* keys added in all four
languages. invalid_passage_fields / invalid_partition_opening_jamb_margin
ship structured JSON details (legacy format read-compat for one beta),
and _errText renders code-first: unknown codes localize, raw English
messages go to the console.
CI: the backend job lints with ruff, refuses a silently skipped HA
harness (import + collect threshold), measures branch coverage over
pure+harness, fails below the committed baseline and uploads
coverage.xml. quality_scale: docs-troubleshooting/examples honestly
done, test-coverage/strict-typing carry staged progress.
User-Visible: yes
Issue: #42
Network failure of the editor runtime is no longer terminal: the loader
re-arms to idle and the next explicit press starts a fresh cycle, while a
fingerprint mismatch on either attempt stays terminal. The toast now says
what actually helps — retry advice for the network, refresh advice for a
foreign build — via one shared lazyLoadFailureMessage helper (new i18n key
editor.retry_advice in en/ru/de).
The field smoke caught a second, deeper bug on the way: Chromium records a
FAILED module in the page module map permanently, so retrying the same URL
(even the cache-busted one) never touched the network again. Every retry
now carries a per-cycle nonce and becomes a genuinely new module request.
A proxy-cached stale entry no longer kills the card silently: the entry
facade is rewritten at build time from a static re-export into a top-level
`try{await import(...)}catch{...}` — importers keep the happy-path
guarantee (await import(entry) still resolves only after
customElements.define), and the catch defines a fallback element with a
localized "reload the page" panel. Content-hashed chunks are served with
`public, max-age=31536000, immutable`, and verifyBundleTree now fails on
orphan chunks that the manifest does not name.
Proofs: loader units for re-arm/terminality/toast wording + an AST check
that both loaders forward the terminality flag; smoke_entry_stale (en/ru)
against a tree without the main chunk; smoke_lazy_editor_chunk extended —
second press after network failure now really opens the editor; pytest for
the immutable header; orphan-tree unit; five new registry mutants.
TESTING.md budget line updated to the #352 ceiling alongside.
Issue: #353
User-Visible: yes
Codex