fix(naturalist): draw the three missing item icons

frog_leg, cooked_frog_leg and snake_egg_block are declared in the behavior
pack and mapped in item_texture.json, but the PNGs were never present, so all
three rendered as missing-texture wherever they appeared. All three already
had lang names, so only the art was absent.

Drawn through scripts/build-textures.py to match the pack's existing style --
small sprite on transparency, muted natural palette, single highlight. The
frog legs share one drumstick routine, raw carrying a green skin tint along
the top contour and cooked a browned crust. snake_egg_block is a clutch of
three eggs reusing the palette of the pack's existing single snake_egg.png,
so the block form reads as a group of the item.

RP bumped to 1.0.3 and mya's pin updated to match, otherwise clients keep
serving the cached pack and never fetch the new files.

Note: naturalist-lite-addon is absent from deploy.yml's PATHS, so CI never
deploys it -- this was applied to the host by hand. That absence is also why
the host sat on RP 1.0.1 while main was already at 1.0.2.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015Gf1kZypRDfPL1YiWUS1LC

naturalist-lite-addon/naturalist_lite_RP/manifest.json

@@ -4,14 +4,26 @@
     "name": "Naturalist Lite Resources",
     "description": "Textures, models, and animations for Naturalist Lite mobs.",
     "uuid": "de1b016a-3cf3-4f75-8076-5a5508ab8b74",
-    "version": [1, 0, 2],
-    "min_engine_version": [1, 21, 0]
+    "version": [
+      1,
+      0,
+      3
+    ],
+    "min_engine_version": [
+      1,
+      21,
+      0
+    ]
   },
   "modules": [
     {
       "type": "resources",
       "uuid": "29da80f3-cffc-4c3b-997d-34f0820cc65b",
-      "version": [1, 0, 2]
+      "version": [
+        1,
+        0,
+        3
+      ]
     }
   ]
 }