build(deps): vendor libvterm at v0.3.3

Problem: Adding support for modern Nvim features (reflow, OSC 8, full
utf8/emoji support) requires coupling libvterm to Nvim internals
(e.g., utf8proc).

Solution: Vendor libvterm at v0.3.3.

cmake.deps/cmake/BuildLibvterm.cmake

@@ -1,8 +0,0 @@
-get_externalproject_options(libvterm ${DEPS_IGNORE_SHA})
-ExternalProject_Add(libvterm
-  DOWNLOAD_DIR ${DEPS_DOWNLOAD_DIR}/libvterm
-  PATCH_COMMAND ${CMAKE_COMMAND} -E copy
-    ${CMAKE_CURRENT_SOURCE_DIR}/cmake/LibvtermCMakeLists.txt
-    ${DEPS_BUILD_DIR}/src/libvterm/CMakeLists.txt
-  CMAKE_ARGS ${DEPS_CMAKE_ARGS}
-  ${EXTERNALPROJECT_OPTIONS})

cmake.deps/cmake/LibvtermCMakeLists.txt

@@ -1,28 +0,0 @@
-cmake_minimum_required(VERSION 3.13)
-project(libvterm C)
-
-add_compile_options(-w)
-
-include(GNUInstallDirs)
-
-include_directories(${CMAKE_SOURCE_DIR}/include)
-include_directories(${CMAKE_BINARY_DIR})
-
-file(GLOB VTERM_SOURCES ${CMAKE_SOURCE_DIR}/src/*.c)
-add_library(vterm ${VTERM_SOURCES})
-install(TARGETS vterm ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
-
-install(FILES include/vterm.h include/vterm_keycodes.h
-  DESTINATION include)
-
-if(NOT WIN32)
-  file(GLOB BIN_SOURCES ${CMAKE_SOURCE_DIR}/bin/*.c)
-  foreach(EXE_C ${BIN_SOURCES})
-    get_filename_component(target_name ${EXE_C} NAME_WE)
-    add_executable(${target_name} ${EXE_C})
-    target_link_libraries(${target_name} vterm)
-    install(TARGETS ${target_name} RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
-  endforeach()
-endif()
-
-# vim: set ft=cmake: