fix(scale): render features + gate SCAMIN on the true physical displa…

[beetlebugorg]

…y scale

S-52 references everything to one calibrated physical Display Scale ([distance on glass]/[distance on earth]), with the display dimensionally calibrated (S-52 Annex C). The renderer instead used three different fixed pixel sizes — 0.35278 mm (typographic point) for symbol/line/text sizing, 0.28 mm (OGC web tile pixel) for SCAMIN gating, and 0.2645 mm (CSS pixel) for the scale readout — none of which is the screen's real pitch. On a dense display this drew every symbol/line/label ~25-30% too small ("like zoomed out") and made SCAMIN features linger past their stated scale (a 1:17999 feature survived to ~1:20000-22000).

Collapse the two render-side constants onto the calibrated pxPitch the readout already uses:

• Feature sizing: multiply icon-size/line-width/text-size/halo (and the pattern raster ratio) by 0.35278/pxPitch in the style builder, so symbols render at their exact S-52 physical mm. S-52 §3.1.5: symbol size is fixed and held constant across zoom.
• SCAMIN: scaminDisplayZoom now returns zoomForScalePhysical(scamin, lat, pxPitch), so a 1:N feature appears exactly when the screen reads 1:N (S-57 B.1 §2.2.7). pxPitch is threaded through buildChartLayers and the in-place latitude re-gate via a getPxPitch callback on ChartSources.

The element rebuilds the style on setPxPitch; the shell pushes the calibration at boot and on change. The baker's OGC-pixel tile floor is left as-is: real screens are finer than 0.28 mm, so the client always gates at or above the baked floor (the safe direction).