feat(vault): model the Art. 77(1) passport scope

[LKSNDRTMLKV]

Addresses #238 — the second half needs dpp-core and stays open. Stacked on feat/battery-import-templates (#237).

Engine-only, deliberately — dpp-core is under review elsewhere, so nothing
here touches it. That constraint decides how much of #238 this can close; see
What this cannot fix below.

The rule

Art. 77(1), verbatim from the OJ:

"From 18 February 2027 each LMT battery, each industrial battery with a
capacity greater than 2 kWh and each electric vehicle battery placed on the
market or put into service shall have an electronic record ('battery
passport')."

Five categories are defined (Art. 3(9), (11), (12), (13), (14)); this article
reaches three. domain::passport_scope is one pure function over values core
already owns, so lifting it into core later is a move rather than a rewrite.

Two qualifiers the article turns on, both easy to lose:

• The threshold is energy, not charge. It says kWh. The Regulation's only
  definition of "rated capacity" — ampere-hours — is scoped "for the purposes
  of this Annex" and does not govern Art. 77(1). The comparison is against
  ratedCapacityKwh, never nominalCapacityAh.
• No rechargeable qualifier. Arts. 7 and 8 both say "rechargeable
  industrial batteries with a capacity greater than 2 kWh". Art. 77(1) does not.

Which way to be wrong

An undeclared capacity is treated as in scope. Exempting on an unknown is
the error that silently switches off a statutory gate; including on an unknown
is friction an operator can end by declaring the capacity, and the note tells
them so. Deriving energy from nominalVoltageV × nominalCapacityAh (both
required) was considered and rejected for the exempting direction — an inference
about a battery is not the ground on which to stop asking for content the law
requires. An unrecognised BatteryType (the enum is #[non_exhaustive]) is
handled the same way, and logs.

What this cannot fix

check_mandatory_content runs inside dpp-core's Passport::transition_to on
first publish. The engine calls that; it cannot skip it. So the concrete
over-demand in #238 — an industrial battery at or below 2 kWh being asked for
content the article exempts — is still present, and needs a core change.

Measured, not assumed: an industrial battery at 1.5 kWh reports
passportScope: voluntary and still returns 34 blockers. Rather than
leave that unexplained, the note says it outright ("this node still applies the
category content gate, which is stricter than the article requires here"), and
a_battery_outside_article_77_is_voluntary_and_still_gated pins both halves —
so if core ever narrows the gate, the test fails and the note goes with it.

The other half of #238 is closed: a portable or SLI passport is now named
voluntary instead of passing silently.

Verified live

batteryType	ratedCapacityKwh	obligation
ev	—	required
lmt	—	required
industrial	64	required
industrial	2.0	voluntary (article says greater than)
industrial	1.5	voluntary
industrial	—	required + note on how to leave scope
portable	—	voluntary
starting-lighting-ignition	—	voluntary

just check green (971 tests), just openapi-check green.

Not core's PassportObligation

dpp_domain::instrument::PassportObligation already exists and answers a
different question, so this type is deliberately named PassportScope:

• Core — an act and a product group: does Reg. (EU) 2023/1542 create a
  passport duty for batteries, and from when (Required/NotRequired/
  DisplacedBy).
• Here — one record: given that the duty exists, does Art. 77(1) reach
  this battery, whose type and capacity decide it.

They compose. Naming both "obligation" would invite a reader to assume one was
the other — the same two-names-one-concept mistake the sector/productGroup
rename was paid for.

Build integrity

Verified against published dpp-core 0.19.0, with the local
[patch.crates-io] override removed, because dpp-core's working tree is one
commit ahead of the published tag and is being edited by someone else. 971 tests
pass either way; CI builds the published pin, so that is the run that counts.
Nothing in this branch touches dpp-core.

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

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🟢 Metrics 25 complexity · 5 duplication

Metric	Results
Complexity	25
Duplication	5

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