ui/phase-19: read-only ship-group inspector + sheet + tab dispatch

Closes Phase 19's UI surface. The inspector dispatches on the
selection variant: local / other groups render class, count, the
four tech levels, mass, cargo (type + amount when loaded),
location (planet name on-orbit, from/to/distance in hyperspace),
and — for local groups only — fleet membership + state. Incoming
groups surface origin / destination / distance / speed and the
inline ETA = ceil(distance / speed); zero speed collapses to the
designer's existing "—" placeholder. Unidentified groups render
just the (x, y) coordinates and the no-data hint, mirroring the
unidentified planet treatment.

Layout / inspector-tab plumbing:
  - inspector-tab.svelte derives selectedShipGroup against the
    rendered report and mounts <ShipGroup /> when the planet
    branch doesn't match. Stale refs (an index that no longer
    resolves after a turn refresh) collapse cleanly to the empty
    state.
  - +layout.svelte mounts <ShipGroupSheet /> alongside the
    existing planet sheet on mobile; both share the
    `effectiveTool === "map"` guard and clear-on-close.

i18n: en + ru both grow ~30 keys under
`game.inspector.ship_group.*`. Adding a key to one without the
other is a TS error (TranslationKey is `keyof typeof en`), so the
Russian mirror stays mandatory.

Tests:
  - inspector-ship-group.test.ts exercises every variant —
    on-planet local, in-hyperspace local, cargo-loaded local,
    foreign, incoming with ETA, incoming with zero speed,
    unidentified, plus the missing-planet `#NN` fallback.
  - tests/e2e/inspector-ship-group.spec.ts is a smoke spec that
    drives the DEV-only synthetic-report loader from /lobby
    through navigation to /games/synthetic-XXX/map.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ui/frontend/src/lib/i18n/locales/ru.ts

@@ -246,6 +246,36 @@ const ru: Record<keyof typeof en, string> = {
 	"game.designer.ship_class.preview.range": "дальность при полной загрузке (св.лет/ход)",
 	"game.designer.ship_class.preview.cargo_capacity": "грузоподъёмность одного корабля",
 	"game.designer.ship_class.preview.unavailable": "—",
+
+	"game.inspector.ship_group.kind.local": "ваша группа",
+	"game.inspector.ship_group.kind.other": "группа другой расы",
+	"game.inspector.ship_group.kind.incoming": "входящая группа",
+	"game.inspector.ship_group.kind.unidentified": "неопознанная группа",
+	"game.inspector.ship_group.field.class": "класс",
+	"game.inspector.ship_group.field.count": "кораблей",
+	"game.inspector.ship_group.field.drive": "двигатели",
+	"game.inspector.ship_group.field.weapons": "оружие",
+	"game.inspector.ship_group.field.shields": "защита",
+	"game.inspector.ship_group.field.cargo_tech": "грузоперевозки",
+	"game.inspector.ship_group.field.mass": "масса",
+	"game.inspector.ship_group.field.cargo_load": "груз на борту",
+	"game.inspector.ship_group.field.location": "расположение",
+	"game.inspector.ship_group.field.from": "из",
+	"game.inspector.ship_group.field.to": "в",
+	"game.inspector.ship_group.field.distance": "оставшееся расстояние",
+	"game.inspector.ship_group.field.speed": "скорость (св.лет/ход)",
+	"game.inspector.ship_group.field.eta": "прибытие (ходов)",
+	"game.inspector.ship_group.field.fleet": "флот",
+	"game.inspector.ship_group.field.state": "состояние",
+	"game.inspector.ship_group.field.coordinates": "координаты",
+	"game.inspector.ship_group.cargo.col": "колонисты",
+	"game.inspector.ship_group.cargo.cap": "промышленность",
+	"game.inspector.ship_group.cargo.mat": "сырьё",
+	"game.inspector.ship_group.cargo.emp": "пусто",
+	"game.inspector.ship_group.cargo.none": "нет",
+	"game.inspector.ship_group.location.in_hyperspace": "в гиперпространстве",
+	"game.inspector.ship_group.fleet.none": "—",
+	"game.inspector.ship_group.unidentified_no_data": "данных нет — известны только координаты",
 };
 
 export default ru;