Characters: one file per character with a world per difficulty

- CharacterNN.sacredK holds the shared hero and one world per difficulty,
  plus an autosave file; the game works in save\characters\_work
- Load window: one row per character, a difficulty dialog on Laden
  (worlds, newer autosaves, "(neu)" starts a new game with the shared
  hero), Umbenennen, delete moves the character to characters\deleted
- The world keeps its own portals and hero position when the shared hero
  is put on
- K and the Esc menu's "Speichern" save directly (quicksave path)
- One-time migration of the old save rows and exported heroes, after a
  backup
- Startup no longer hangs in the game's foreground loop (0x810af0)
- Text overrides apply to our own text ids too; shared cUI_Button2
  helpers in game/ui/button.h

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

tools/names.txt

@@ -329,3 +329,18 @@
 0x006116c0 cEngine::dropItem                  # the player's drop into the world
 0x005fc910 cObjectManager::RemoveFromMap      # (id), ret 4
 0x00819580 Options_PickupAuto                 # PICKUPAUTO from the config (0 all, 1 valuable, 2 gold)
+0x0061d190 LoadHeroFile                       # cdecl (path, 1, 0): a hero file onto the player hero (whole object, position too)
+0x0061cda0 cEngine::SaveHero                  # cdecl (path): the player hero as a hero file
+0x0061b790 cEngine::Load                      # (path, quiet), ret 8: reads a GAME.PAK
+0x00619c90 cEngine::Save                      # (path), ret 4; render thread, engine +0x54 & 0x40
+0x0060dc00 cEngine::InitGame                  # (int), ret 4: new game, start hero
+0x0071c520 cUI_Savegame::Action               # (action), ret 4: 2 save, 4 load, 8 delete, 10 rescan, 0xb default
+0x0071e330 cUI_Savegame::Scan                 # (dir, multiplayer), ret 8: "./SAVE/*.PAK"
+0x0071be90 cUI_Savegame::SendSaveLoad         # (kind, row): engine event 0xf
+0x00755ac0 cCommand_armaPlay::execute         # posts 0x8002 (mode, argument) to the main window
+0x007d7c40 Session_Instance
+0x007d7cf0 Session::SetHeroClass              # (class) -> +0x44, ret 4
+0x00417e50 GameSetup_Instance                 # 0x12e6c bytes; +0 set by both character-screen starts
+0x006bb870 cUI_EscMenu::BuildLines            # line actions; "Spielstaende" text 0x41b at 0x6bc1f7
+0x00810af0 BringWindowToFront                 # (hwnd, timeout), ret 8; loops forever with timeout -1
+0x0072ad60 cUI_Button2::SetCaption            # (text id, font), ret 8 -> +0xa4 / +0xa0