Fix up a few cmake and link things

1. Make fmt work from the vendored fmt
2. Add the cmake flags so we can use std::filesystem back to 10.13
   in the fs::space and modify the create_directories to use a path
   at least
3. Vendor in CLI11

cli/CMakeLists.txt

@@ -1,20 +1,9 @@
-add_executable(clap-wrapper-cli
+project(clap-wrapper-cli)
+add_executable(${PROJECT_NAME}
         src/main.cpp
 )
 
-CPMAddPackage(NAME CL11
-        GITHUB_REPOSITORY CLIUtils/CLI11
-        GIT_TAG v2.4.2)
-
-# TODO: deduplicate this with the vendored fmt -
-#       for some reason, the cli won't link
-#       if we include the vendored version
-CPMAddPackage(
-        NAME fmt
-        GITHUB_REPOSITORY fmtlib/fmt
-        GIT_TAG 11.0.2
-        OPTIONS
-        "FMT_INSTALL ON"
-)
-
-target_link_libraries(clap-wrapper-cli PUBLIC CLI11::CLI11 fmt::fmt)
+target_include_directories(${PROJECT_NAME}  PRIVATE ../libs/fmt )
+target_include_directories(${PROJECT_NAME}  PRIVATE ../libs/CLI11 )
+target_link_libraries(${PROJECT_NAME} PRIVATE clap-wrapper-compile-options-public)
+target_link_libraries(${PROJECT_NAME} PRIVATE clap-wrapper-shared-detail)

cli/src/main.cpp

@@ -3,8 +3,13 @@
 #include <fstream>
 #include <stdexcept>
 #include <CLI/CLI.hpp>
+
+#define FMT_HEADER_ONLY
 #include <fmt/format.h>
 
+#include "detail/clap/fsutil.h"
+
+
 // rationale against using std::filesystem is that
 // it requires macOS 10.15, but our min supported version is 10.13 atm
 #ifdef _WIN32
@@ -48,15 +53,15 @@ std::string get_absolute_path(const std::string& path)
  * Creates a directory if it doesn't exist.
  * @param path Path of the directory to create.
  */
-void create_directory(const std::string& path)
+void create_directory(const fs::path& path)
 {
-  if (CREATE_DIRECTORY(path.c_str()) != 0)
+  try
   {
-    if (!DIRECTORY_EXISTS)
-    {
-      throw std::runtime_error("Failed to create directory: " + path +
-                               " Error: " + std::strerror(errno));
-    }
+    fs::create_directories(path);
+  }
+  catch (fs::filesystem_error &fs)
+  {
+    throw fs;
   }
 }