Diagonal screw tubes, laid by a 45° drag (t35)

- Tubes run in eight directions: a drag at about 45° lays a diagonal run, R cycles all eight.
- Diagonal runs carry grains at the straight rate (120 grains/s), join straight tubes and belts,
  keep grains in at the corners, pass water, and carry bars level.
- New part ids 11-14 (saved ids are never renumbered); tube checks use an IS_TUBE table.
- New test/t_diag_tubes.js (85 checks).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/play.py

@@ -695,6 +695,23 @@ with sync_playwright() as p:
     check('square wall drag can also place a diagonal', ev(f'Array.from({{length:4}}, (_,k)=>blockP[({bby}-12+k)*BW+{bbx}-5+k]).every(c=>c===BP_WALL)'))
     pg.keyboard.press('Control+z'); settle(60)
 
+    # Diagonal tubes use real mouse placement, preview arrows, R and picking.
+    check('select screw tube', select('3', "piece().id === 'tube'"))
+    ev('GAME.pieceDir.tube = 0')
+    directions = []
+    for _ in range(8):
+        directions.append(ev('GAME.pieceDir.tube'))
+        pg.keyboard.press('r'); settle(40)
+    check('R cycles eight tube directions', directions == list(range(8)) and ev('GAME.pieceDir.tube') == 0)
+    drag(lambda: blk(bbx - 5, bby - 12), lambda: blk(bbx - 2, bby - 9))
+    check('diagonal tube drag places four down-right blocks', ev(f'Array.from({{length:4}}, (_,k)=>[blockP[({bby}-12+k)*BW+{bbx}-5+k],blockV[({bby}-12+k)*BW+{bbx}-5+k]]).every(([c,v])=>c===BP_TUBE && v===5)'))
+    pg.mouse.move(*blk(bbx - 4, bby - 11)); settle(60)
+    check('diagonal hover names its direction', ev(f"hoverInfo(({bbx}-4)*4+1,({bby}-11)*4+1).t1.includes('down-right')"))
+    pg.mouse.click(*blk(bbx - 4, bby - 11), button='middle'); settle(60)
+    check('picking a diagonal tube keeps its direction', ev("piece().id === 'tube' && GAME.pieceDir.tube === 5"))
+    pg.screenshot(path=str(out / '04-diagonal-tubes.png'))
+    pg.keyboard.press('Control+z'); settle(60)
+
     # 6. ingot mold: click to place, pour, bars drop below, vacuum them
     ok = select('3', "piece().id === 'ingotmold'")
     check('E cycles to the ingot mold', ok)