rpg_walk: save, main menu, load; action card texts are translated

Covers the empty dialog box after loading a save and the untranslated
action cards in battle. Docs: the world is built from engine mods, not a
novel engine.

manifest.json

@@ -3,7 +3,7 @@
   "name": "RPG World",
   "version": "1.0.0",
   "author": "ct",
-  "description": "Top-down tile world in the spirit of RPG Maker on top of the novel engine: maps of square tiles in three layers (back, main, front) with a collision layer, walking on the grid with WASD or the arrows, events that talk, teleport or start battles with the action key E/F or on touch, random encounters. A map is a logical scene, so entry scenarios, ambience, saving and the dialog box work on maps unchanged; battles run on the turn-based platform with the game's battle core and return to the same cell. Scenario actions: rpg.battle, rpg.teleport.",
+  "description": "Top-down tile world in the spirit of RPG Maker on top of the 2D engine mods: maps of square tiles in three layers (back, main, front) with a collision layer, walking on the grid with WASD or the arrows, events that talk, teleport or start battles with the action key E/F or on touch, random encounters. A map is a logical scene, so entry scenarios, ambience, saving and the dialog box work on maps unchanged; battles run on the turn-based platform with the game's battle core and return to the same cell. Scenario actions: rpg.battle, rpg.teleport.",
   "category": "gameplay",
   "sources": [
     "src/**/*.cs"