Steam and cooling plant for the five-press fleet; utilities re-based

New page docs/steam-cooling.html (site /demos/steam-cooling/): the
utility plant as a clickable process diagram. Steam side: raw water,
softener and dosing, feed tank with heat-pump feedwater recovery, feed
pumps, a bank of two 500 kg/h boilers (third for N+1 as an option),
separator and metering, optional accumulator, blowdown, the 10 bar
header with a valved, metered branch and trap per press, drip legs and
condensate return. Cooling side: Newbilt's press outlets are open (max.
2 bar), so returns drain to a warm tank, pass the heat pump, an optional
dry cooler and a plate heat exchanger to a cold buffer tank, and VFD
pumps feed the 20 to 25 C header at ~10 bar to every press, the
extruders and the central hydraulic oil cooler; the chiller loop
(three 250 kW air-cooled modules at 40 C ambient, fourth as option) stays
closed and clean. Galvanics cooling (12 to 20 C) is a separate circuit.
Operating cases (launch, Duplex system 1, five presses, one module down)
show demand against installed capacity; design basis with sources,
equipment schedule, RFQ questions. Static SVG, no per-frame work.

Design basis at Newbilt's per-machine figures: steam 750 to 900 kg/h,
cooling 652.5 kW (625 presses, 15 extruders, 12.5 hydraulics), 305 to
540 l/min circulating. Also found: Newbilt's 53 l/min at ~60 C out is
~140 kW, above its 125 kW peak; listed as a re-quote question.

Re-based in the same commit:
- scale.md: electrical table (chiller bank ~210 to 325 kW electrical,
  plant peak ~430 to 700 kW, ~950 to 1,330 kW with electric steam),
  grid 800 to 1,000 kVA (1,250 to 1,600 with electric steam, Schedule
  4 past 1,000 kW), tariff 4.5M to 6.8M THB/yr, battery ~1 h of chiller
  peak, boiler and chiller banks, biomass up to ~550 t/yr at 1.5 M
  records, utilities money line.
- sustainability.md, biomass.md: same figures; electric steam 5.2M to
  6.0M THB/yr mature, 1.6M to 1.8M early; fuel saving 4.0M to 5.4M.
- utilities CSV: boiler bank, chiller bank with HX and tanks, softener
  and loop treatment re-sized; baseline 23.98M-41.63M -> 30.07M-51.33M.
- total-investment.md: re-size as an added-scope row (+185k / +294k
  USD); headline 4.7M to 8.9M unchanged until the investment re-base.
- pressing-line, equipment-suppliers, facility-security, fleet
  calculator (boiler 1000 kg/h, chiller 750 kW), plant page detail
  texts; README, landing page, build.sh.

README.md

@@ -164,6 +164,14 @@ The detail lives in dedicated documents:
   (for artists, labels and any other customer), and optionally launch a
   fan-funded campaign that the plant presses and ships to each fan once
   enough have pre-ordered, with refunds if not
+- [Steam and cooling](docs/steam-cooling.html): the utility plant for the
+  five-press fleet as a clickable process diagram: water treatment, feed
+  tank and heat recovery, a bank of two 500 kg/h boilers, the steam header
+  and condensate return, and process cooling with three 250 kW chillers,
+  a plate heat exchanger, warm and cold tanks and a branch to every press,
+  extruder and the hydraulic oil cooler; operating cases from the launch
+  press to one module down, the design basis, an equipment schedule and
+  the open questions for the boiler and chiller RFQs
 - [Plant operation page](docs/plant-operation.html): a single static page
   animating the mature plant as a simulated SCADA overview at real cycle
   times: the Newbilt Duplex and two Classic presses, the Pheenix Alpha
@@ -277,6 +285,7 @@ docs/
 ├── roadmap.md             Next steps in dependency order
 ├── scale.md               Rough project sizing on one page
 ├── site-candidates.md     Land options and the checks before choosing
+├── steam-cooling.html     Steam and cooling plant diagram, five-press fleet
 ├── sustainability.md      Energy, water, materials commitments
 ├── traceability.md        Process logging and per-order traceability
 └── worker-safety.md       Training, clean rooms, PPE