feat(input): map the keypad (numpad) keys

VMCTL_KEYS carried only NumLock, not the keypad block — so any keypad evdev
code sent in CMD_INPUT{KEY} was dropped on both paths: uinput device A never
declared the keybit, and the QMP qcode lookup returned NULL.

Add the full keypad in sorted evdev positions (the table is bsearch'd):
kp_0..kp_9, kp_add/subtract/multiply/divide, kp_enter, kp_decimal, kp_equals,
kp_comma. Both the uinput keybits and the QMP qcodes derive from this one
table, so both paths pick the keys up.

Add test_keymap pinning the strictly-ascending-by-evdev invariant (bsearch
precondition + no duplicates) and the keypad lookup.

Bump 0.3.13.

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.16)
 # Single source of truth for the version: CI passes -DVMSIG_VERSION=${TAG#v}, so the project
 # version (-> libvgpu-perception SONAME/.so version) and the .deb version come from one tag.
-set(VMSIG_VERSION "0.3.12" CACHE STRING "Release version (MAJOR.MINOR.PATCH); CI passes the tag")
+set(VMSIG_VERSION "0.3.13" CACHE STRING "Release version (MAJOR.MINOR.PATCH); CI passes the tag")
 project(vmsig VERSION ${VMSIG_VERSION} LANGUAGES C)
 
 set(CMAKE_C_STANDARD 17)
@@ -276,6 +276,13 @@ target_include_directories(vmsig_uinputlayouttest PRIVATE
 target_compile_options(vmsig_uinputlayouttest PRIVATE -Wall -Wextra)
 add_test(NAME uinputlayout COMMAND vmsig_uinputlayouttest)
 
+add_executable(vmsig_keymaptest src/test/test_keymap.c)
+target_link_libraries(vmsig_keymaptest PRIVATE vmsig)
+target_include_directories(vmsig_keymaptest PRIVATE
+        ${CMAKE_CURRENT_SOURCE_DIR}/src/si/input/include)
+target_compile_options(vmsig_keymaptest PRIVATE -Wall -Wextra)
+add_test(NAME keymap COMMAND vmsig_keymaptest)
+
 add_executable(vmsig_memwritetest src/test/test_memwrite.c)
 target_link_libraries(vmsig_memwritetest PRIVATE vmsig Threads::Threads)
 target_include_directories(vmsig_memwritetest PRIVATE