Key bindings layer: skills on 1-7, weapon sets on F1-F7

Raw WM_KEYDOWN/WM_KEYUP are handled in both window procedures (the game
swaps 0x8110d0 and 0x8122a0 with SetWindowLong; 0x8110d0 is the in-game
one). Bound keys are swallowed and post the original hotkey's key event
to the kernel, so F-keys work and bindings are layout independent
([keys] in sacred_re.ini). Replaces the WASD hotkey remap and the digit
swap; W/A/S/D and the digit row no longer reach the game. Skill keys
still cast through the right mouse button. Enabled switches removed.

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

docs/wasd.md

@@ -49,9 +49,13 @@ badly; targets near the stepwise-updated position make it arrive and stop.
 Keys reach the game as `cEvent_key` (category 4; key at +6/+8, modifiers at
 +0xa) through the kernel queue to `cEngine::ReceiveEvent` (`0x618130`), which
 offers them to `cUI_Manager::ReceiveEvent` (`0x757120`) first. Both compare
-`toupper(key)` (`0x84aa86`). The mod swallows W/A/S/D there (auto-repeat events
-would trigger the hotkeys) and rewrites the replacement keys into the old
-letters; the temporary bindings are listed in `docs/todo.md`.
+`toupper(key)` (`0x84aa86`). Presses come from `WM_CHAR` (the character), releases
+from `WM_KEYUP` (the virtual key), so keys without a character (F-keys) never
+reach the hotkeys. The key bindings (`src/mods/input.cpp`) handle the raw
+`WM_KEYDOWN`/`WM_KEYUP` instead: W/A/S/D and the digit row are kept from the
+game, bound keys post the original hotkey's key event (`Kernel_Instance`
+`0x808490`, `cKernel::PostEvent` `0x808930`); the temporary bindings for the
+old W/A/S actions are listed in `docs/todo.md`.
 
 Hotkeys found: engine A (pick up nearby), P (pause), Q/W/E/R/B/Space
 (`cEngine::UseActionSlot`), ^ (console), Esc, Ctrl+B/F/X/Z (Z quicksave); UI