Print Gold and Silver's Pokédex heights and weights in metric units

The #DEX page prints the US cart's height in feet and inches, with the foot and inch tiles, and its weight in pounds; the localized carts print metres and kilograms ("TAI  ???m", "PDS  ???kg"). A mod can now give a species its metric height and weight the way it can on Red/Blue: mod.content.pokemon:patch(id, { dexEntry = { heightM = ..., weightKg = ... } }). src/core/gen2/PokedexText.lua copies them onto the #DEX entry beside the cart's own values, and the page then prints them with one decimal and a comma, right-aligned before the "m" and "kg" labels, "???" until the species is caught; the printout draws the same body, and the plain page drawn without the cache's dex sheet prints the metric values as it prints the imperial ones. The Gen 2 pokemon schema declares the dexEntry fields the #DEX page reads.

The Pokédex resolves the "m" and "kg" labels when it opens (PokedexMenu.new) rather than on every frame.

docs/modding/reference/registries.md

@@ -941,6 +941,7 @@ do not.
 | `catchRate` | integer 0..255 | yes |
 | `cry` | cries id | no |
 | `dex` | integer >= 1 | yes |
+| `dexEntry` | {heightM?, kind?, text?, text2?, weightKg?} | no |
 | `eggGroups` | list of string | no |
 | `eggGroupsRaw` | integer 0..255 | no |
 | `eggMoves` | list of moves id | no |