ui/phase-23: turn-report view with twenty sections and TOC

Replaces the Phase 10 report stub with a scrollable orchestrator that
renders every FBS array as a dedicated section (galaxy summary, votes,
player status, my/foreign sciences, my/foreign ship classes, battles,
bombings, approaching groups, my/foreign/uninhabited/unknown planets,
ships in production, cargo routes, my fleets, my/foreign/unidentified
ship groups). A sticky table of contents (a <select> on mobile),
"back to map" affordance, IntersectionObserver-driven active-section
highlight, and SvelteKit Snapshot-based scroll save/restore round out
the view.

GameReport gains six new fields (players, otherScience, otherShipClass,
battleIds, bombings, shipProductions); decodeReport, the synthetic-
report loader, the e2e fixture builder, and EMPTY_SHIP_GROUPS extend
in lockstep. ~90 new i18n keys land in en + ru together.

The legacy-report parser is extended to populate the new sections from
the dg/gplus text formats (Your Sciences, <Race> Sciences, <Race> Ship
Types, Bombings, Ships In Production). Ships-in-production prod_used
is derived through a new pkg/calc.ShipBuildCost helper; the engine's
controller.ProduceShip refactors to call the same helper without any
behaviour change (engine tests stay unchanged and green). Battles
remain in the parser's Skipped list — the legacy text carries no
stable per-battle UUID.

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

pkg/calc/planet.go

@@ -11,3 +11,29 @@ func PlanetProduceShipMass(L, Mat, Res float64) float64 {
 	}
 	return (L + Mat/Res) / (10 + 1/Res)
 }
+
+// ShipBuildCost returns the total per-turn cost (production units) to
+// build one ship of empty mass shipMass on a planet that currently
+// holds material stockpile and has natural resources. The cost is the
+// ship's production cost ([ShipProductionCost]) plus the cost of
+// farming any missing material from the planet (the missing-material
+// volume divided by the planet's resources rating).
+//
+// resources is expected to be positive in normal play; the helper
+// guards against a non-positive value by collapsing the material-
+// farming term to zero, which keeps callers numerically stable on
+// pathological synthetic data. Mirrors the per-iteration math inside
+// the engine's controller.ProduceShip so both surfaces — and the
+// legacy-report-to-json dev tool that needs to derive prod_used from
+// percent — share the same formula.
+func ShipBuildCost(shipMass, material, resources float64) float64 {
+	matNeed := shipMass - material
+	if matNeed < 0 {
+		matNeed = 0
+	}
+	matFarm := 0.
+	if resources > 0 {
+		matFarm = matNeed / resources
+	}
+	return ShipProductionCost(shipMass) + matFarm
+}