Payap model v4: colour store, silos, two-storey finishing and print block

User, October 2026: ground-floor colour store plus outdoor silos; a
two-storey block at the east end with packaging below and printing plus
print and packaging stock above; in-house printing not decided, so the
print room is reserved only.

Model (rebuilt live in FreeCAD 26.3 after checking a copy of the saved
file for user edits; parametric check plot 150->160 m and upper floor
3.8->4.2 m passed):
- factory 128 x 25 m, plot 150 m (14.1 rai), corridor 98 m, fire wall
  at 106 m, new params crane_x (runway end = press hall end, 92 m) and
  mezz_z (+3.8 m);
- galvanics open to stamper prep (wall kept only on the material area
  and electrical side);
- colour store 10 m bay (~180 m2): two racking rows, ~100 pallet
  positions on 4 levels (estimate), weighing and mixing, vacuum
  conveying station; indoor silos replaced by regrind bins;
- 4 outdoor PVC silos (2 black, 2 standard colours, ~50 m3 each,
  estimate), big-bag filling station, buried conveying lines;
- finishing and print block 14 x 25 m: ground floor trim, optical
  inspection, QC, packaging (tables, shrink wrap, pallet wrapper), stair
  (Arch Stairs) and goods lift; upper floor print room (reserved), print
  stock, packaging materials.
New docs/cnx_vinyl_parametric_payap-block.png with both block levels.

Docs: site-candidates Payap section rewritten (areas ~3,800 m2 under
roof, ~4,630 m2 of floor), crane doc (98 m corridor, runway ends at the
press hall), README bullet and layout line.

docs/crane-workshop-tours.md

@@ -319,9 +319,13 @@ The Payap scenario model
 resolves that conflict. Mastering and cutting, the offices and IT move
 into a separate office building, so only production sits under the
 crane. The tour then starts in the office building, at the cutting-room
-window and the listening room, and crosses a covered link into an 82 m
+window and the listening room, and crosses a covered link into a 98 m
 corridor. That is longer than the 45 to 55 m assumed below, because the
-press hall keeps room for ten more Classics. The model also draws the
+press hall keeps room for ten more Classics and a colour store sits
+before it. In that model the crane runway ends at the press hall:
+finishing and packaging sit beyond it in a two-storey block with the
+print room and stocks upstairs, which the crane cannot serve, so loads
+there move by forklift and goods lift. The model also draws the
 five-press fleet of October 2026; the sketch above still shows the
 earlier fleet (one Duplex and two Classics).