Fleet calculator: material, energy and labour cost, revenue and P&L

User, October 2026: add calculation for material cost, PVC, carton,
chemicals, labour etc. and revenue from sales.

New "Money a year" card (and a "Prices and money" input card):
- revenue: standard records at the standard price, specials with the
  premium, title services per title (revenue-model.md 3.50 to 4.60
  blended, +0.60 to 1.70, 580 to 1,730 USD a title);
- materials and packaging: PVC from the compound tonnage (rejects in,
  trim back as regrind), labels per pressed record, inner sleeves,
  printed jackets, shrink wrap, shipping cartons (estimate), maintenance;
- stamper making: lacquer blanks and styli per side (estimate), nickel,
  silver and chemistry per electroformed part (revenue model: 60 to 150
  USD a three-generation set);
- energy from the fleet: machines, chiller and compressors at the hours
  run plus an estimated base load, roof PV off, PEA 3.2.2 blended rate and
  demand charge; steam from the presses running time at the biomass heat
  price (biomass.md); the start fleet lands in scale.md 4.3 to 6.4M THB;
- loaded labour per role (revenue-model.md wages; cutting engineer an
  estimate), headcount now also counts QC, maintenance and cutting;
- overheads, EBITDA, depreciation of capex (total-investment.md start
  fleet plan plus or minus each Duplex system and Classic), operating
  profit, payback; per-record cost bar;
- Adverse / Central / Favourable presets from the revenue model ranges,
  USD / THB / EUR display; ladder gains revenue and EBITDA columns.
At the defaults (1 M records, 20 % specials): revenue 4.42M USD, direct
cost 1.86 USD a record (revenue model central 1.94), EBITDA 2.23M.

README bullet; revenue-model.md links the calculator from its operating
picture.

README.md

@@ -182,8 +182,12 @@ The detail lives in dedicated documents:
   stampers that fleet needs, drawn as a live schematic of the machine
   park with the stamper line (lathe, Pheenix galvanics, Sibert prep)
   feeding it, each station counted from the galvanics cycle times;
-  every assumption is editable, with its source, and a scenario can be
-  shared by link
+  plus the money a year: revenue (standard, specials, title services),
+  PVC, labels, sleeves, jackets, cartons, lacquers, plating chemistry,
+  electricity and steam, loaded labour, overheads, EBITDA, depreciation
+  and payback, with the revenue model's adverse, central and favourable
+  cases and USD, THB or EUR; every assumption is editable, with its
+  source, and a scenario can be shared by link
 - [Test site](site/README.md): `site/` builds https://cnxvinyl.lol/, the
   internal test site with demo pages from `docs/` (the plant operation
   page first) and any static site we want to share by link; Gitea Actions